Cephalosporin analogues

ABSTRACT

The invention deals with Cephalosporin Analogues of the formula: ##STR1## wherein R 1  is amino or amino substituted with a pharmaceutically acceptable carboxylic acyl protective group for the amino substituents in cephalosporin compounds or with benzyl, phenethyl or trityl, and 
     R 2  is carboxy or a pharmaceutically acceptable ester of said carboxy group employed in cephalosporin compounds, and pharmaceutically acceptable salts thereof, and their use as antimicrobial agents.

This is a division, of now U.S. Pat. No. 4,264,597, application Ser. No.043,706, filed May 30, 1979.

The present invention relates to new cephalosporin analogues andpharmaceutically acceptable salts thereof. More particularly, it relatesto new cephalosporin analogues and pharmaceutically acceptable saltsthereof which have antimicrobial activities, particularly antifungalactivities, and to processes for the preparation thereof, topharmaceutical composition comprising the same, and to a method of usingthe same therapeutically for treatment of infectious diseasesparticularly fungal infection, in human being and animals.

Accordingly, it is one object of the present invention to provide newcephalosporin analogues and pharmaceutically acceptable salts thereof,which are highly active against wide variety of pathogenicmicroorlganisms, particularly fungus.

Another object of the present invention is to provide processes for thepreparation of new cephalosporin analogues and pharmaceuticallyacceptable salts thereof.

A further object of the present invention is to provide pharmaceuticalcomposition comprising, as active ingredients, said cephalosporinanalogues and pharmaceutically acceptable salts thereof.

Still further object of the present invention is to provide a method fortreatment of infectious diseases caused by pathogenic bacteria,particularly fungus, in human being and animals.

The object cephalosporin analogues of the present invention are noveland can be represented by the following formula (I): ##STR2## wherein X₁is --O-- or --S--;

R¹ is amino or a substituted amino group;

R² is carboxy or a protected carboxy group; and the heavy solid linemeans single or double bond.

It is to be understood that there may be one or more stereoisomericpair(s) such as optical and/or geometrical isomers due to asymmetriccarbon atom(s) and/or double bond(s) in the molecula of the objectcompounds (I) and the related compounds (e.g. other object compounds,starting compounds, etc.), of the present invention, and these isomersare also included within the scope of the present invention. Theparticulars of such isomers will be made clearer in the followingexplanation.

For example, two configurations may be given due to the 6th position ofthe fused β-lactam nuclei of the object compounds of the presentinvention. Accordingly, it is to be noted that the nucleus wherein X is--O-- and the heavy solid line is a double bond; the one wherein X is--O-- and the heavy solid line is a single bond; the one wherein X is--S-- and the heavy solid line is a double bond; and the one wherein Xis --S-- and the heavy solid line is a single bond; which have the sameconfigurations to those of natural cephalosporin compounds, will begiven by the nomenclatures, "1-oxadethia-2-oxo-3-cephem","1-oxadethia-2-oxocepham", "2-oxo-3-cephem" and "2-oxocepham",respectively. And then, the said nuclei are represented by the formula:##STR3## (Note: In the formula, the mark " " means β-configuration andthe dotted line means α-configuration.), throughout in thisspecification.

Furthermore, as one skilled in the art can readily appreciate, in casethat the heavy solid line is a single bond, the substituent at the 4thposition can be in either α or β configuration.

The cephalosporin analogues (I) of the present invention can be preparedby the following processes. ##STR4## wherein R¹, R², X and the heavysolid line are each as defined above;

R^(1a) is a protected amino;

R^(1b) is a protected amino;

R^(1c) is a substituted amino having a protected amino;

R^(1d) is a substituted amino having an amino;

R^(2a) is a protected carboxy;

R³ a is hydrogen and R^(3b) is a group of the formula: ##STR5## in whichR⁴ is lower alkyl, or R^(3a) and R^(3b) are linked together to form agroup of the formula: =P(R⁵)₃ in which R⁵ is lower alkyl, aryl ordi(lower)alkylamino.

The starting compounds (II) and (III) are novel and can be prepared bythe processes as illustrated by the following scheme. ##STR6## whereinR¹, R², X, R^(3a) and R^(3b) are each as defined above;

R⁶ and R⁷ are each lower alkyl;

R^(7') is alkylidene;

R⁸ and R⁹ are each hydroxy protective group;

Y is halogen; and

R¹⁰ is a substituent on amino.

Suitable pharmaceutically acceptable salts of the object cephalosporinanalogues (I) are conventional non-toxic salts and may include a saltwith an inorganic base, for example, a metal salt such as an alkalimetal salt (e.g. sodium salt, potassium salt, etc.) and an alkalineearth metal salt (e.g. calcium salt, magnesium salt, etc.), ammoniumsalt, etc., a salt with an organic base, for example, an organic aminesalt (e.g. trimethylamine salt, triethylamine salt, pyridine salt,picoline salt, dicyclohexylamine salt, N,N'-dibenzylethylenediaminesalt, etc.), etc., an organic acid salt (e.g. maleate, tartrate,methanesulfonate, benzenesulfonate, toluenesulfonate, etc.), aninorganic acid salt (e.g. hydrochloride, hydrobromide, sulfate,phosphate, etc.), or a salt with an amino acid (e.g. arginine, asparticacid, lysine, glutamic acid, etc.), and the like.

Particulars for the definitions of the present invention are illustratedin details as follows.

The term "lower" is intended to mean 1 to 6 carbon atom(s) and "higher"is intended to mean 7 to 18 carbon atoms respectively unless otherwiseprovided.

"Substituted amino" may include an amino group substituted with suitablesubstituent(s) which is conventionally used in cephalosporins andpenicillins field as the substituent of amino group at their 7th or 6thposition.

Suitable "substituted amino" may include acylamino, and an amino groupsubstituted with a group other than the acyl group, such asar(lower)alkyl (e.g. benzyl, phenethyl, trityl, etc.) or the like.

Suitable protected carboxy may include esterified carboxy in which saidester may be the ones such as lower alkyl ester (e.g. methyl ester,ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester,t-butyl ester, pentyl ester, t-pentyl ester, hexyl ester,1-cyclopropylethyl ester, etc.); lower alkenyl ester (e.g. vinyl ester,allyl ester etc.); lower alkynyl ester (e.g. ethynyl ester, propynylester, etc.); mono(or di or tri)halo(lower)alkyl ester (e.g. 2-iodoethylester, 2,2,2-trichloroethyl ester, etc.); lower alkanoyloxy(lower)alkylester (e.g. acetoxymethyl ester, propionyloxymethyl ester,butyryloxymethyl ester, valeryloxymethyl ester, pivaloyloxymethyl ester,hexanoyloxymethyl ester, 2-acetoxyethyl ester, 2-propionyloxyethylester, etc.); lower alkanesulfonyl(lower)alkyl ester (e.g. 2-mesylethylester etc.); ar(lower)alkyl ester, for example, phenyl(lower)alkyl esterwhich may have one or more suitable substituent(s) (e.g. benzyl ester,4-methoxybenzyl ester, 4-nitrobenzyl ester, phenethyl ester, tritylester, diphenylmethyl ester, bis(methoxyphenyl)methyl ester,3,4-dimethoxybenzyl ester, 4-hydroxy-3,5-ditertiarybutylbenzyl ester,etc.); aryl ester which may have one or more suitable substituent(s)(e.g. phenyl ester, tolyl ester, tertiarybutylphenyl ester, xylyl ester,mesityl ester, cumenyl ester, etc.), and the like.

Suitable "protected amino" and "protected amino moiety" in the terms "asubstituted amino having a protected amino" may include acylamino and anamino group substituted with other conventional protective groups thanthe acyl groups such as ar(lower)alkyl as aforementioned, and the like.

Suitable "acyl" and "acyl moiety" in the terms "acylamino" as mentionedabove may include carbamoyl, aliphatic acyl, aromatic acyl andheterocyclic acyl, wherein said aromatic acyl and heterocyclic acyl areeach intended to mean an acyl containing aromatic ring and heterocyclicring, respectively.

Suitable example of said acyl may be illustrated as follows:

Aliphatic acyl such as lower or higher alkanoyl (e.g. formyl, acetyl,succinyl, hexanoyl, heptanoyl, stearoyl, etc.);

lower or higher alkoxycarbonyl (e.g. methoxycarbonyl, ethoxycarbonyl,t-butoxycarbonyl, t-pentyloxycarbonyl, heptyloxycarbonyl, etc.);

lower or higher alkanesulfonyl (e.g. methanesulfonyl, ethanesulfonyl,etc.); or the like;

Aromatic acyl such as

aroyl (e.g. benzoyl, toluoyl, naphthoyl, etc.);

ar(lower)alkanoyl (e.g. phenylacetyl, phenylpropionyl, etc.);

aryloxycarbonyl (e.g. phenoxycarbonyl naphthyloxycarbonyl, etc.);

aryloxy(lower)alkanoyl (e.g. phenoxyacetyl, phenoxypropionyl, etc.);

arylglyoxyloyl (e.g. phenylglyoxyloyl, naphthylglyoxyloyl, etc.);

ar(lower)alkoxycarbonyl (e.g. benzyloxycarbonyl,diphenylmethoxycarbonyl, etc.);

arenesulfonyl (e.g. benzenesulfonyl, p-toluenesulfonyl, etc.); or thelike;

Heterocyclic acyl such as

heterocycliccarbonyl (e.g. thenoyl, furoyl, nicotinoyl, etc.);

heterocyclic(lower)alkanoyl (e.g. thienylacetyl, thiazolylacetyl,tetrazolylacetyl, etc.);

heterocyclicglyoxyloyl (e.g. thiazolylglyoxyloyl, thienylglyoxyloyl,etc.); or the like; in which suitable heterocyclic moiety in the terms"heterocycliccarbonyl". "heterocyclic(lower)alkanoyl" and"heterocyclicglyoxyloyl" as mentioned above means, in more detail,saturated or unsaturated, monocyclic or polycyclic heterocyclic groupcontaining at least one heteroatom such as an oxygen, sulfur, nitrogenatom and the like. And, especially preferable heterocyclic group may beheterocyclic group such as

unsaturated 3 to 8-membered heteromonocyclic group containing 1 to 4nitrogen atom(s), for example, pyrrolyl, pyrrolinyl, imidazolyl,pyrazolyl, pyridyl and its N-oxide, dihydropyridyl, pyrimidyl,pyrazinyl, pyridazinyl, triazolyl (e.g. 4H-1,2,4-triazolyl,1H-1,2,3-triazolyl, 2H-1,2,3-triazolyl, etc.), tetrazolyl (e.g.1H-tetrazolyl, 2H-tetrazolyl, etc.), etc.;

saturated 3 to 8-membered heteromonocyclic group containing 1 to 4nitrogen atom(s), for example, pyrrolidinyl, imidazolidinyl, piperidino,piperazinyl, etc.;

unsaturated condensed heterocyclic group containing 1 to 4 nitrogenatom(s), for example, indolyl, isoindolyl, indolizynyl, benzimidazolyl,quinolyl, isoquinolyl, indazolyl, benzotriazolyl, etc.;

unsaturated 3- to 8-membered heteromonocyclic group containing 1 to 2oxygen atom(s) and 1 to 3 nitrogen atom(s), for example, oxazolyl,isoxazolyl, oxadiazolyl, (e.g. 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl,1,2,5-oxadiazolyl, etc.) etc.;

saturated 3 to 8-membered heteromonocyclic group containing 1 to 2oxygen atom(s) and 1 to 3 nitrogen atom(s), for example, morpholinyl,sydnonyl, etc.;

unsaturated condensed heterocyclic group containing 1 to 2 oxygenatom(s) and 1 to 3 nitrogen atom(s), for example, benzoxazolyl,benzoxadiazolyl, etc.;

unsaturated 3 to 8-membered heteromonocyclic group containing 1 to 2sulfur atom(s) and 1 to 3 nitrogen atom(s), for example, thiazolyl,isothiazolyl, thiadiazolyl (e.g. 1,2,3-thiadiazolyl, 1,2,4-thiadiazolyl,1,3,4-thiadiazolyl, 1,2,5-thiadiazolyl, etc.), dihydrothiazinyl, etc.;

saturated 3 to 8-membered heteromonocyclic group containing 1 to 2sulfur atom(s) and 1 to 3 nitrogen atom(s), for example, thiazolidinyl,etc.;

unsaturated 3 to 8-membered heteromonocyclic group containing 1 to2-sulfur atom(s), for example, thienyl, dihydrodithiinyl,dihydrodithiolyl, etc.;

unsaturated condensed heterocyclic group containing 1 to 2 sulfuratom(s) and 1 to 3 nitrogen atom(s), for example, benzothiazolyl,benzothiadiazolyl, etc.;

unsaturated 3 to 8-membered heteromonocyclic group containing an oxygenatom, for example, furyl, etc.;

unsaturated 3 to 8-membered heteromonocyclic group containing an oxygenatom and 1 to 2 sulfur atom(s), for example, dihydrooxathiinyl, etc.;

unsaturated condensed heterocyclic group containing 1 to 2 sulfuratom(s), for example, benzothienyl, benzodithiinyl, etc.;

unsaturated condensed heterocyclic group containing an oxygen atom and 1to 2 sulfur atom(s), for example, benzoxathiinyl, etc. and the like.

The acyl moiety as stated above may have 1 to 10, same or different,suitable substituent(s) such as lower alkyl; lower alkoxy (e.g. methoxy,ethoxy, propoxy, etc.); lower alkylthio (e.g. methylthio, ethylthio,etc.); lower alkylamino (e.g. methylamino, etc.); cyclo(lower)-alkyl(e.g. cyclopentyl, cyclohexyl, etc.); cyclo(lower)-alkenyl (e.g.cyclohexenyl; cyclohexadienyl, etc.); halogen; amino; protected amino;hydroxy; protected hydroxy; cyano; nitro; carboxy; protected carboxy;sulfo; sulfamoyl; imino; oxo; amino(lower)alkyl (e.g. aminomethyl,aminoethyl, etc.); a group of the formula: =N-OR¹¹ wherein R¹¹ ishydrogen, lower alkyl (e.g., methyl, ethyl, propyl, isopropyl, butyl,pentyl, hexyl, etc.), lower alkenyl (e.g. vinyl, allyl, 2-butenyl,etc.), lower alkynyl (e.g. ethynyl, 2-propynyl, etc.) orcyclo(lower)alkyl (e.g. cyclopropyl, cyclopentyl, cyclohexyl, etc.); orthe like.

In this connection, when the acyl moiety has a group of the formula:=N-OR¹¹, wherein R¹¹ is as defined above, as substituent(s), there aregeometrical isomers (syn and anti isomers) due to the presence of doublebond. And, for example, the syn isomer means one geometrical isomerhaving the group of the formula: ##STR7## And the corresponding antiisomer means the other geometrical isomer having the group of theformula: ##STR8##

Suitable "lower alkyl" may include one which may be branched, forexample, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl,pentyl, hexyl and the like, and preferably 1 to 2 carbon atom(s).

Suitable "aryl" may include phenyl, tolyl, xylyl, mesityl, cumenyl,naphthyl and the like.

Suitable "di(lower)alkylamino" may include dimethylamino, diethylamino,dipropylamino, methylethylamino and the like.

Suitable "alkylidene" may include one which may be branches, forexample, methylidene, ethylidene, propylidene, isopropylidene,butylidene, isobutylidene, t-butylidene, pentylidene, hexylidene and thelike.

Suitable "hydroxy protective group" may include acyl and otherconventional protective groups than the acyl groups such asar(lower)alkyl as aforementioned or the like.

Suitable "halogen" may include chlorine, bromine, fluorine and iodine.

Suitable "substituent or amino" may include acyl, ar(lower)alkyl (e.g.benzyl, phenethyl, trityl, etc.) and the like.

Preferable examples of R¹ may be amino or acylamino, more preferablyamino,

aryloxy(lower)alkanoylamino, most preferably phenoxy(lower)alkanoylamino(e.g. phenoxyacetamido, phenoxypropionamido, etc.);

ar(lower)alkoxycarbonylamino, most preferablyphenyl(lower)alkoxycarbonylamino (e.g. benzyloxycarbonylamino,phenethyloxycarbonylamino, etc.);

ar(lower)alkanoylamino which may have lower alkoxyimino, most preferablyphenyl(lower)alkanoylamino which may have lower alkoxyimino (e.g.phenylacetamido, phenylpropionamido, 2-methoxyimino-2-phenylacetamido,2-ethoxyimino-2-phenylacetamido, 2-propoxyimino-2-phenylacetamido,2-isopropoxyimino-2-phenylacetamido, 2-butoxyimino-2-phenylacetamido,2-pentyloxyimino-2-phenylacetamido, 2-hexyloxyimino-2-phenylacetamido,etc.);

heterocyclic(lower)alkanoylamino which may have lower alkoxyimino, mostpreferably thiazolyl(lower)-alkanoylamino having lower alkoxyimino andamino or lower alkanoylamino (e.g.2-methoxyimino-2-(2-aminothiazol-4-yl)acetamido,2-methoxyimino-2-(2-formamidothiazol-4-yl)acetamido,2-ethoxyimino-2-(2-aminothiazol-4-yl)acetamido,2-propoxyimino-2-(2-aminothiazol-4-yl)acetamido,2-isopropoxyimino-2-(2-aminothiazol-4-yl)acetamido,2-butoxyimino-2-(2-aminothiazol-4-yl)acetamido,2-pentyloxyimino-2-(2-aminothiazol-4-yl)acetamido,2-pentyloxyimino-2-(2-formamidothiazol-4-yl)acetamido,2-hexyloxyimino-2-(2-aminothiazol-4-yl)acetamido, etc.); and preferableexample of R² may be carboxy or ar(lower)-alkoxycarbonyl, mostpreferably phenyl(lower)alkoxycarbonyl (e.g. benzyloxycarbonyl,phenethyloxycarbonyl, etc.).

The processes for preparing the object compounds of the presentinvention are explained in details in the following.

Process 1

The object compound (Ia) or a salt thereof can be prepared by subjectingthe compound (II) or its reactive derivative at the formyl group or asalt thereof to cyclization.

Suitable salt of the compound (II) may include an acid addition saltsuch as an organic acid salt (e.g. acetate, maleate, tartrate,benzenesulfonate, toluenesulfonate, etc.) or an inorganic acid salt(e.g. hydrochloride, hydrobromide, sulfate, phosphate, etc.); a metalsalt (e.g. sodium salt, potassium salt, calcium salt, magnesium salt,etc.); ammonium salt; an organic amine salt (e.g. triethylamine salt,dicyclohexylamine salt, etc.), and the like.

Suitable reactive derivative at the formyl group of the compound (II)may include conventional reactive derivative at the formyl group andreactive derivative having equivalent workability to the compound (II)in this reaction. Suitable example of such reactive derivative mayinclude acetal (e.g. dimethyl acetal, diethyl acetal, etc.), hemiacetal,hydrate (diol), thioacetal, hemithioacetal, mono (or di)acylated dioland the like.

In case that the compound (II), in which R^(3a) and R^(3b) are linkedtogether to form a group of the formula=P(R⁵)₃ wherein R⁵ is as definedabove, is used as the starting compound, the present reaction is usuallycarried out in around neutral condition or in the presence of a base asmentioned hereinafter. The reaction is usually carried out in a solventsuch as benzene, methylene chloride, dimethylsulfoxide, ethyl acetate,tetrahydrofuran or any other solvent which does not adversely affect thereaction. The reaction temperature is not critical, and the reaction ispreferably carried out at ambient temperature or under warming.

In the case that the compound (II), in which R^(3a) is hydrogen andR^(3b) is a group of the formula: ##STR9## wherein R⁴ is as definedabove, is used as the starting compound, the present reaction ispreferably carried out in the presence of a strong base such as alkalimetal hydride (e.g. sodium hydride, lithium hydride, etc.), alkalineearth metal hydride (e.g., calcium hydride, etc.), alkali metalt-alkoxide (e.g. sodium t-butoxide, potassium t-butoxide, etc.),ar(lower)alkyl alkali metal (e.g. trityl sodium, trityl lithium, etc.),aryl alkali metal (e.g. phenyl lithium, etc.) or the like. The reactionis usually carried out in a solvent such as benzene, tetrahydrofuran,dioxane or any other solvent which does not adversely affect thereaction. The reaction temperature is not critical, and the reaction isusually carried out at ambient temperature, under warming or heating.

Process 2

The object compound (Ia) a salt thereof can be prepared by oxidizing thecompound (III) or its reactive derivative at the hydroxymethyl group ora salt thereof.

Suitable salt of the compound (III) can be referred to the onesexemplified as the salt of the compound (II).

Suitable reactive derivative at the hydroxymethyl group of the compound(III) may include the compound wherein the hydroxymethyl group of thecompound (III) is transformed into methyl group having an acid residuesuch as halogen (e.g. chlorine, bromine, etc.), arenesulfonyloxy (e.g.p-toluenesulfonyloxy, p-nitrobenzenesulfonyloxy, etc.), haloformyloxy(e.g. chloroformyloxy, etc.) or the like.

Suitable oxidizing agent to be used in this oxidation reaction mayinclude conventional ones which can oxidize hydroxymethyl or reactivederivatives of the hydroxymethyl group to formyl.

In case that the starting compound has 2-hydroxyacetoxy group at the 4thposition of azetidinone ring, said oxidizing agent may include (1) anactivated dimethylsulfoxide formed by a reaction of dimethylsulfoxideand dicyclohexylcarbodiimide, dimethylsulfoxide and acetic anhydride,dimethylsulfoxide and phosphorus pentoxide, dimethylsulfoxide and sulfurtrioxide-pyridine, dimethylsulfoxide and keteneimine, dimethylsulfoxideand chlorine, dimethylsulfoxide and mercuric acetate, dimethylsulfideand N-chlorosuccinimide, dimethylsulfide (or methylphenylsulfide) andchlorine, etc.; (2) a chrome compound such as chromiumtrioxide-pyridine, chromium trioxide-sulfuric acid, alkali metaldichromate (e.g. sodium dichromate, potassium dichromate, etc.), loweralkyl chromate (e.g. t-butyl chromate, etc.) and the like.

The oxidation using dimethylsulfoxide and dicyclohexylcarbodiimide ispreferably carried out in the presence of a proton-donor such as an acid(e.g. phosphoric acid, trifluoroacetic acid, dichloroacetic acid, etc.),a mixture of acid and base (e.g. trifluoroacetic acid-pyridine,phosphoric acid-pyridine, etc.) or the like.

The present oxidation reaction is carried out without or in the presenceof an acid or a base, and it is optionally selected according to a kindof oxidizing agent to be used.

The present oxidation is carried out without or with solvent such asbenzene, toluene, chloroform, methylene chloride, carbon tetrachloride,diethyl ether, dimethylformamide, dimethylsulfoxide or any other solventwhich does not adversely affect the reaction, and the solvent isoptionally selected according to a kind of oxidizing agent to be used.

In case that the starting compound of the present oxidation reaction isin a form of reactive derivatives at the hydroxymethyl group, suitableoxidizing agent may include dimethylsulfoxide and the like. The presentoxidation is preferably carried out in the presence of a base (e.g.sodium bicarbonate, triethylamine, etc.).

The reaction temperature of the oxidation reaction of this process isnot critical, and the reaction is carried out under cooling, at ambienttemperature, under warming or under heating. The reaction temperature isoptionally selected, for example, according to a kind of oxidizing agentto be used.

By the present oxidation reaction, there is produced the compound of theformula (II), and said compound (II), without isolation, can be cyclizedaccording to the method mentioned in Process 1 to give the objectcompound (Ia).

Process 3

The object compound (Ic) or a salt thereof can be prepared by subjectingthe compound (Ib) or a salt thereof to elimination reaction of the7-amino protective group.

Suitable salt of the compound (Ib) may include a metal salt, ammoniumsalt, an organic amine salt and the like as aforementioned.

The present elimination reaction is carried out in accordance with aconventional method such as hydrolysis; reduction; elimination usingLewis acid; a method by reacting the compound (Ib) wherein theprotective group is acyl group with iminohalogenating agent and thenwith iminoetherifying agent, and, if necessary, subjecting the resultingcompound to hydrolysis; or the like.

The hydrolysis may include a method using an acid or base or hydrazineand the like. These methods may be selected depending on the kind of theprotective groups to be eliminated.

Among these methods, hydrolysis using an acid is one of the common andpreferable method for eliminating the protective group such assubstituted or unsubstituted alkoxycarbonyl (e.g. t-pentyloxycarbonyl,etc.), alkanoyl (e.g. formyl, etc.), cycloalkoxycarbonyl, substituted orunsubstituted aralkoxycarbonyl (e.g. benzyloxycarbonyl, substitutedbenzyloxycarbonyl, etc.), substituted phenylthio, substitutedaralkylidene, substituted alkylidene, substituted cycloalkylidene, orthe like. Suitable acid may include an organic or an inorganic acid, forexample, formic acid, trifluoroacetic acid, benzenesulfonic acid,p-toluenesulfonic acid, hydrochloric acid and the like, and preferableacid is an acid which can be easily removed from the reaction mixture bya conventional manner such as distillation under reduce pressure, forexample, formic acid, trifluoroacetic acid, hydrochloric acid, etc. Theacid suitable for the reaction can be selected according to the kind ofprotective group to be eliminated. When the elimination reaction isconducted with the acid, it can be carried out in the presence orabsence of a solvent. Suitable solvent may include an organic solvent,water or a mixed solvent thereof. When trifluoroacetic acid is used, theelimination reaction may be preferably carried out in the presence ofanisole.

Among the protective group, the acyl group can be generally eliminatedby conventional hydrolysis. In case that the acyl group is halogensubstituted-alkoxycarbonyl or 8-quinolyloxycarbonyl, they are eliminatedby treating with a heavy metal such as copper, zinc or the like.

The reductive elimination is generally applied for eliminating theprotective group, for example, haloalkoxy carbonyl (e.g.trichloroethoxycarbonyl etc.), substituted or unsubstitutedaralkoxycarbonyl (e.g. benzyloxycarbonyl, substituted benzyloxycarbonyletc.), 2-pyridylmethoxycarbonyl, etc. Suitable reduction may include,for example, reduction with an alkali metal borohydride (e.g. sodiumborohydride, etc.), catalytic reduction and the like.

The elimination reaction using Lewis acid is carried out substantiallyin the same manner as described in Process 6.

Suitable iminohalogenating agent used in a method as mentioned above mayinclude phosphorus halide (e.g. phosphorus trichloride, phosphoruspentachloride, phosphorus tribromide, phosphorus pentabromide, etc.),phosphorus oxychloride, thionyl chloride, phosgene and the like.

The reaction temperature is not critical, and the reaction is usuallycarried out at ambient temperature or under cooling.

Suitable iminoetherifying agent reacted with thus obtained reactionproduct may include an alcohol, metal alkoxide and the like. Suitablealcohol may include alkanol (e.g. methanol, ethanol, propanol,isopropanol, butanol, t-butanol, etc.) which may be substituted withalkoxy (e.g. methoxy, ethoxy, propoxy, isopropoxy, butoxy, etc.).Suitable metal alkoxide may include alkali metal alkoxide (e.g. sodiumalkoxide, potassium alkoxide, etc.), alkaline earth metal alkoxide (e.g.calcium alkoxide, barium alkoxide, etc.) and the like.

The reaction temperature is not critical, and the reaction is usuallycarried out under cooling or at ambient temperature.

Thus obtained product is, if necessary, subjected to hydrolysis. Thehydrolysis can be readily carried out by pouring the reaction mixtureobtained above into water, but there may be previously added ahydrophilic solvent (e.g. methanol, ethanol, etc.), a base (e.g. alkalimetal bicarbonate, trialkylamine, etc.) or an acid (e.g. dilutedhydrochloric acid, acetic acid, etc.) to the water.

The reaction temperature is not critical and may be suitably selected inaccordance with the kind of the protective group of the amino group andthe elimination method as mentioned above, and the present reaction ispreferably carried out under a mild condition such as under cooling, atambient temperature or slightly elevated temperature.

The present invention includes, within its scope, the case that theprotected carboxy is transformed into the free carboxy group accordingto reaction conditions etc. in the course of the reaction or inpost-treatment.

Process 4

The object compound (Id) or a salt thereof can be prepared by subjectingthe compound (Ic) or its reactive derivatives at the amino group or asalt thereof to introduction reaction of the substituent(s) on the aminogroup.

Suitable reactive derivatives at the amino group of the compound (Ic)may include conventional ones such as Schiff's base type imino or itstautomeric enamine type derivatives formed by the reaction of thecompound (Ic) with a carbonyl compound (e.g. aldehyde, ketone, etc.),isocyanate; a silyl derivatives formed by the reaction of the compound(Ic) with a silyl compound [e.g. bis(trimethylsilyl)-acetamide,trimethylsilylacetamide, etc.]; a derivatives formed by reaction of thecompound (Ic) with phosphorus trichloride or phosgene, or the like.

Suitable salt of the compound (Ic) can be referred to the onesexemplified for the compound (II).

The present introduction reaction of the substituent(s) on the aminogroup is carried out by reacting the compound (Ic) or its reactivederivatives at the amino group or a salt thereof with an agent which canintroduce the substituent(s) on the amino group.

Suitable said agent may include an acylating agent, ar(lower)alkylhalide (e.g. benzyl chloride, trityl chloride, etc.) and the like.

The acylating agent to be used for the present reaction may include oneof the formula:

    R.sup.12 -OH                                               (XXX)

wherein R¹² is acyl, or its reactive derivatives or a salt thereof.

In case that the compound (XXX) or its reactive derivatives or a saltthereof is used as the agent which introduces substituent(s) on theamino group, an acyl group for R¹² is introduced on an amino group atthe 7th position of the compound (Ic).

Suitable acyl can be referred to the one exemplified hereinbefore.

Suitable reactive derivatives of the compound (XXX) may include an acidhalide, an acid anhydride, an activated amide, an activated ester, andthe like. The suitable example may be an acid chloride; an acid azide; amixed acid anhydride with an acid such as substituted phosphoric acid(e.g. dialkylphosphoric acid, phenylphosphoric acid, diphenylphosphoricacid, dibenzylphosphoric acid, halogenated phosphoric acid, etc.),dialkylphosphorous acid, sulfurous acid, thiosulfuric acid, sulfuricacid, alkylcarbonic acid, aliphatic carboxylic acid (e.g. pivalic acid,pentanoic acid, isopentanoic acid, 2-ethylbutyric acid ortrichloroacetic acid, etc.) or aromatic carboxylic acid (e.g. benzoicacid, etc.); a symmetrical acid anhydride; an activated amide withimidazole, 4-substituted imidazole, dimethylpyrazole, triazole ortetrazole; an activated ester [e.g. cyanomethyl ester, methoxymethylester, dimethyliminomethyl [(CH₃)₂ N⁺ =CH-] ester, vinyl ester,propargyl ester, p-nitrophenyl ester, 2,4-dinitrophenyl ester,trichlorophenyl ester, pentachlorophenyl ester, mesyl phenyl ester,phenylazophenyl ester, phenyl thioester, p-nitrophenyl thioester,p-cresyl thioester, carboxymethyl thioester, pyranyl ester, pyridylester, piperidyl ester, 8-quinolyl thioester, or an ester withN,N-dimethylhydroxylamine, 1-hydroxy-2-(1H)-pyridone,N-hydroxysuccinimide, N-hydroxyphthalimide or1-hydroxy-6-chloro-1H-benzotriazole, and the like. These rectivederivatives can be optionally selected from them according to the kindof the compound (XXX) to be used.

The salts of the compound (XXX) may be salts with an inorganic base suchas an alkali metal salts (e.g. sodium or potassium salt) or an alkalineearth metal salt (e.g. calcium or magnesium salt), a salt with anorganic base such as trimethylamine, triethylamine, dicyclohexylamine orthe like.

The reaction of the compound (Ic) with the compound (XXX) is usuallycarried out in a conventional solvent such as water, acetone, dioxane,acetonitrile, chloroform, methylene chloride, ethylene chloride,tetrahydrofuran, ethyl acetate, N,N-dimethylformamide, pyridine or anyother organic solvent which does not adversely influence to thereaction. Among these solvents, hydrophilic solvents may be used in amixture with water.

When the compound (XXX) is used in free acid form or its salt form inthe reaction, the reaction is preferably carried out in the presence ofa conventional condensing agent such as carbodiimide compound (e.g.N,N'-dicyclohexylcarbodiimide,N-cyclohexyl-N'-morpholinoethylcarbodiimide,N-cyclohexyl-N'-(4-diethylaminocyclohexyl)-carbodiimide,N,N'-diethylcarbodiimide, N,N'-diisopropylcarbodiimide,N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide, etc.),N,N'-carbonylbis(2-methylimidazole),pentamethyleneketene-N-cyclohexylimine,diphenylketene-N-cyclohexylimine, alkoxyacetylene,1-alkoxy-1-chloroethylene, trialkyl phosphite, ethyl polyphosphate,isopropyl polyphosphate, phosphorus oxychloride, phosphorus trichloride,thionyl chloride, oxalyl chloride, triphenylphosphine,N-ethylbenzisoxazolium salt, N-ethyl-5-phenyl-isoxazolium-3'-sulfonate,1-(p-chlorobenzenesulfonyloxy)-6-chloro-1H-benzotriazole, Vismeierreagent [e.g. (chloromethylene)dimethylammonium chloride, a compoundformed by the reaction of dimethylformamide with phosphorus oxychloride,etc.] or the like.

The reaction may be also carried out in the presence of an inorganic oran organic base such as an alkali metal bicarbonate, alkali metalcarbonate, tri(lower)alkylamine, pyridine, N-(lower)alkylmorphorine,N,N-di(lower)alkylbenzylamine, N,N-di(lower)alkylaniline, or the like.When the base or the condensing agent is in liquid, it can be used alsoas a solvent. The reaction temperature is not critical, and the reactionis usually carried out under cooling or at ambient temperature.

In this reaction, there may occur partially or nearly completeisomerization between syn and anti geometry of the compound (XXX)wherein acyl group for R¹² has a group of the formula: =N-OR¹¹ whereinR¹¹ is as defined above, in the course of the activation process thereofor the reaction with the compound (Ic), depending on surrounding such asreaction conditions or the like. Generally, such isomerization tends tobe equilibrated toward the more stable anti-geometry. Under suchchemical behaviors of the compound (XXX), in case of preparing the synisomer of the object compound (Id) selectively and preparing it in goodyield, it is to be noted that it is essential to use syn isomer of thecompound (XXX) as a starting compound and to select the reactionconditions suitable for producing the syn isomer selectively and in goodyield. For example, for this purpose, the acylation reaction in thisprocess is more preferably conducted by reacting the compounds (Ic) and(XXX) in the presence of a condensing agent such as Vilsmeier reagent,etc. and in a reaction condition such as around neutral.

Process 5

The object compound (Ie) or a salt thereof can be prepared by reducingthe compound (Ia) or a salt thereof.

Suitable salts of the compound (Ia) can be referred to the ones asexemplified for the compound (II).

The present reduction can be carried out, for example, by using acombination of a metal (e.g. zinc, zinc amalgam, e.t.c) and an organicor inorganic acid (e.g. acetic acid, propionic acid, hydrochloric acid,e.t.c); by catalytic hydrogenation in the presence of a conventionalmetallic catalyst and the like.

The present reduction is usually carried out in a solvent such asacetone, dioxane, acetonitrile, benzene, hexane, chloroform, methylenechloride, ethylene chloride, tetrahydrofuran, ethyl acetate or any othersolvents which do not adversely affect the reaction.

The reaction temperature is not critical and the reaction is usuallycarried out under cooling or at ambient temperature.

In this reduction, there is produced a mixture of α and β isomers at 4thposition, and said isomers can be separated by conventional methods suchas column chromatography or the like.

Process 6

The object compound (Ig) or a salt thereof can be prepared by subjectingthe compond (If) or a salt thereof to elimination reaction of thecarboxy protective group.

Suitable salt of the compound (If) can be referred to the acid additionsalt exemplified for the compound (II).

In the present elimination reaction, conventional methods used in theelimination reaction of the carboxy protective group, for example,hydrolysis, reduction, elimination using Lewis acid, etc. areapplicable. When the carboxy protective group is an ester, it can beeliminated by hydrolysis or elimination using Lewis acid. The hydrolysisis preferably carried out in the present of an acid.

Suitable acid may include an organic acid (e.g. formic acid, aceticacid, propionic acid, etc.) and an inorganic acid (e.g. hydrochloricacid, hydrobromic acid, sulfuric acid, etc.).

The present hydrolysis is usually carried out in an organic solvent,water or a mixed solvent thereof.

The reaction temperature is not critical, and it may be suitablyselected in accordance with the kind of the protective group of thecarboxy and the elimination method.

The elimination using Lewis acid is preferable to eliminate substitutedor unsubstituted ar(lower)alkyl ester and carried out by reacting thecompound (Ia) or a salt thereof with Lewis acid such as boron trihalide(e.g. boron trichloride, boron trifluoride, etc.), titanium tetrahalide(e.g. titanium tetrachloride, titanium tetrabromide, etc.), tintetrahalide (e.g. tin tetrachloride, tin tetrabromide, etc.), aluminumhalide (e.g. aluminum chloride, aluminum bromide, etc.), trihaloaceticacid (e.g. trichloroacetic acid, trifluoroacetic acid, etc.) or thelike. This elimination reaction is preferably carried out in thepresence of cation trapping agents (e.g. anisole, phenol, etc.) and isusually carried out in a solvent such as nitroalkane (e.g. nitromethane,nitroethane, etc.), alkylene halide (e.g. methylene chloride, ethylenechloride, etc.), diethyl ether, carbon disulfide or any other solventwhich does not adversely affect the reaction. These solvents may be usedas a mixture thereof. The reaction temperature is not critical, and thereaction is usually carried out under cooling, at ambient temperature orunder warming.

Reduction can be applied preferably for elimination of the protectivegroup such as halo(lower)alkyl ester (e.g. 2-iodoethyl,2,2,2-trichloroethyl, etc.) or the like. The reduction method applicablefor the elimination reaction may include, for example, reduction byusing a combination of a metal (e.g. zinc, zinc amalgam, etc.) or a saltof chrome compound (e.g. chromous chloride, chromous acetate, etc.) andan organic or inorganic acid (e.g. acetic acid, propionic acid,hydrochloric acid, etc.); and conventional catalytic reduction in thepresence of a conventional metallic catalyst.

The present elimination reaction of the carboxy protective groupincludes, within its scope, the cases that protected amino and/orprotected carboxy group in the compound (If) is transformed into freeamino and/or carboxy group according to reaction conditions and kinds ofthe protective groups in the course of the reaction and/or inpost-treatment of the reaction.

Process 7

The object compound (Ii) or a salt thereof can be prepared by subjectingthe compound (Ih) or a salt thereof to elimination reaction of theprotective group of the amino.

Suitable salt of the compound (Ih) can be referred to the ones asexemplified for the compound (II).

The present elimination reaction is carried out substantially in thesame manner as illustrated in Process 3.

The present invention includes, within its scope, the case that theprotected carboxy is transformed into the free carboxy group accordingto reaction conditions etc. in the course of the reaction or inpost-treatment.

In the aforementioned reactions and/or the post-treating of thereactions of the present invention, the aforementioned geometricalisomer and/or tautomeric isomer may occasionally be transformed into theother geometrical isomer and/or tautomeric isomer and such cases are tobe also included in the scope of the present invention.

In case that the object compound (I) has free carboxy group and/or freeamino group, it may be transformed into its pharmaceutically acceptablesalt as aforementioned by a conventional method.

The processes for preparing the starting compounds of the presentinvention are explained in detail in the following.

Suitable salts of the compounds (IV), (XI), (XII), (XIII), (XVIII),(XX), (XXI), (XXV), (XXVa), (XXVb), (XXVI), (XXVIa), (XXVII), (XXVIIa),(XXVIII), and (XXIX) can be referred to the ones as exemplified for thecompound (II).

Suitable salts of the compounds (V), (VI), (VII), (VIII), (IX), (X),(XI), (XIV), (XV), (XVI), (XVII), (XIX) AND (XXIV) can be referred tothe ones as exemplified for the compound (Ib).

Suitable reactive derivatives at the carboxy group of the compounds (V)and (XIX) may include an acid halide, an acid anhydride, an activatedamide, an activated ester as mentioned in Process 4 and the like.

Preparation A: (1) processes of (IV)+(V)→(VI) [Process A-1];(IV)+(XIX)→(VIII) [Process A-1] and (XIII)→(XXVa) [Process A-1]

The compounds (VI) and (VIII) or a salt thereof can be prepared byreacting the compound (IV) or a salt thereof with the compound (V) orits reactive derivatives at the carboxy group or a salt thereof and byreacting the compound (IV) or a salt thereof with the compound (XIX) orits reactive derivatives at the carboxy group or a salt thereof,respectively; and the compound (XXVa) or a salt thereof can be preparedby subjecting the compound (XIII) or its reactive derivatives at theamino group or a salt thereof to introduction reaction of thesubstituent(s) on the amino group.

The present reaction can be carried out substantially in the same methodas illustrated in Process 4.

(2) a process of (X)+(XI)→(XII) [Process A-1)]

The compound (XII) or a salt thereof can be prepared by reacting thecompound (X) or a salt thereof with the compound (XI) or its reactivederivatives at the hydroxy group or a salt thereof.

Suitable reactive derivatives at the hydroxy group of the compound (XI)wherein R¹⁰ is acyl, may include the ones as exemplified for reactivederivatives of the compound (XXX). Suitable reactive derivatives at thehydroxy group of the compound (XI) wherein R¹⁰ is, for example,ar(lower)alkyl, may include the ones wherein the hydroxy group issubstituted with an acid residue such as halogen, acyloxy (e.g.benzenesulfonyloxy, tosyloxy, etc.) and the like.

The reaction conditions can be referred to the ones as illustrated inProcess 4.

Preparation B: Processes of (VI)→(VII) [Process A-1)]; (XVII)→(XV)[Process A-3)] and (XXIX)→(III) [Process C].

The compounds (VII), (XV) and (III) or a salt thereof can be prepared bysubjecting the compounds (VI), (XVII) and (XXIX) or a salt thereof toelimination reaction of the protective group of the hydroxy,respectively.

The present elimination reaction is carried out in accordance with aconventional method such as hydrolysis, reduction, elimination using aLewis acid or the like. These methods can be referred to the ones asillustrated in Process 6.

Preparation C: Processes of (VII)→(VIII) [Process A-1)] and (XV)→(X)[Process A-2)];

The compounds (VIII) and (X) or salts thereof can be prepared bysubjecting the compounds (VII) and (XV) or salts thereof to introductionreaction of the protective group of the hydroxy.

The introduction method depends upon the kind of protective groupintroduced on the hydroxy. In case that the acyl groups are introduced,the present reaction is carried out according to a similar manner tothat of Process 4.

The reaction is usually carried out in a conventional solvent such asmethylene chloride or any other solvents which do not adversely affectthe reaction.

The reaction temperature is not critical, and the reaction is usuallycarried out under cooling or at ambient temperature.

Preparation D: Processes of (VIII)→(IX) [Process A-1)]; (VII)→(XIV)[Process A-2)]; and (VI)→(XVI) [Process A-3].

The compounds (IX), (XIV) and (XVI) or salts thereof can be prepared byhalogenating the compounds (VIII), (VII) and (VI) or a salt thereof,respectively.

The present reaction may be carried out by using halogenating agentssuch as halogen (e.g., chlorine, bromine, etc.) or the like.

The present reaction is usually carried out in a conventional solventsuch as methylene chloride, chloroform or any other solvents which donot adversely affect the reaction.

The reaction temperature is not critical, and the reaction is usuallycarried out under cooling or at ambient temperature.

Preparetion E: Processes of (IX)→(X) [Process A-1)]; (XIV)→(XV) [ProcessA-2)] and (XVI)→(XVII) [Process A-3)].

The compounds (X), (XV) and (XVII) or salts thereof can be prepared bysubjecting the compounds (IX), (XIV) and (XVI) or salts thereof toCyclization reaction.

The present reaction is preferably carried out in the presence ofinorganic metal salt such as silver salts (e.g. silvertetrafluoroborate, silver perchloride, etc.), stannic chloride, zincchloride or the like.

The present reaction may be carried out in the presence of base such assilver oxide or the like.

The reaction is usually carried out in a solvent such as methylenechloride, toluene, chloroform or any other solvents which do notadversely affect the reaction.

The reaction temperature is not critical, and the reaction is preferablycarried out under cooling or at ambient temperature.

Preparation F: Processes of (X)→(XIII) [Process A-1)] and (XII)→(XXVa)[Process A-1)].

The compounds (XIII) and (XXVa) or salts thereof can be prepared bysubjecting the compounds (X) and (XII) or salts thereof to ring-openingreaction, respectively.

The present reaction may be carried out in accordance with aconventional method such as hydrolysis, especially by using an acid.Suitable acids may include d-camphorsulfonic acid besides the ones asexemplified in Process 3.

The present reaction is usually carried out in a conventional solventsuch as methylene chloride, acetone or any other solvents which do notadversely affect the reaction.

The reaction temperature is not critical, and the reaction is usuallycarried out under cooling, at ambient temperature or under warming.

Preparation G: Processes of (XVIII)+(XIX)→(XX) [Process B-1)] and(XXII)+(XIX)→(XXIII) [Process B-2)].

The compounds (XX) or a salt thereof and (XXIII) can be prepared byreacting the compounds (XVIII) or a salt thereof and (XXII) with thecompounds (XIX) or its reactive derivatives at the carboxy group or asalt thereof, respectively.

The reaction conditions can be referred to the ones as illustrated inProcess 4.

Preparation H: A process of (XX)→(XXVb) [Process B-1)]

The compound (XXVb) or a salt thereof can be prepared by isomerizing thecompound (XX) or a salt thereof.

The present reaction can be carried out in the presence of bases asexemplified in Process 4.

The present reaction is usually carried out in a conventional solventsuch as benzene or any other solvents which do not adversely affect thereaction.

The reaction temperature is not critical and the reaction is usuallycarried out under cooling or at ambient temperature.

Preparation I: A process of (XXIII)+(XXIV)→(XXVIIa) [Process B-2)]

The compound (XXVIIa) or a salt thereof can be prepared by reacting thecompound (XXIII) with the compound (XXIV) or a salt thereof.

The reaction is usually carried out in a conventional solvent such asbenzene or any other solvents which do not adversely affect thereaction.

The reaction temperature is not critical and the reaction is usuallycarried out at ambient temperature or under heating.

Preparation J: Processes of (XX)→(XXI) [Process B-1)]; (XXI)→(XXVIa)[Process B-1)] and (XXV)→(XXVI) [Process C].

The compounds (XXI), (XXVIa) and (XXVI) or salts thereof can be preparedby ozonolysis of the compounds (XX), (XXI) and (XXV) or salts thereofand if necessary, reducing the resulting compound.

The present ozonolysis reaction is carried out by reacting the compounds(XX), (XXI) and (XXV) with ozone.

The present reaction is usually carried out in a solvent such as ethylacetate, methyl acetate or any other solvents which do not adverselyaffect the reaction.

The reaction temperature is not critical and the reaction is preferablycarried out under cooling or at ambient temperature.

In case that the corresponding ozonide compound is produced in thepresent reaction, the compounds (XXI), (XXVIa) and (XXVI) or saltsthereof can be obtained by further reducing the ozonide compound with aconventional reducing agent such as sodium sulfite, sodium bisulfite,dimethyl sulfide trimethylphosphite or the like.

The present reaction is usually carried out in a solvent such as ethylacetate or any other solvents which do not adversely affect thereaction.

The reaction temperature is not critical and the reaction is preferablycarried out under cooling or at ambient temperature.

Preparation K: A process of (XXVI)→(XXVII) [Process C]

The compound (XXVII) or a salt thereof can be prepared by reducing thecompound (XXVI) or a salt thereof.

The present reduction can be carried out by a conventional method whichis applied to the reduction of --CO-- group to the corresponding--CH(OH)-- group, for example, by using a combination of a metal (e.g.zinc, etc.) and an organic or inorganic acid (e.g. acetic acid,propionic acid, hydrochloric acid, etc.), lithium borohydride, sodiumborohydride, aluminum amalgam; metal amalgam (e.g., aluminum amalgam,etc.), catalytic hydrogenation or the like.

The present reaction is preferably carried out in a solvent such asmethylene chloride, tetrahydrofuran or any other solvents which do notadversely affect the reaction.

The reaction temperature is not critical and the reaction is preferablycarried out under cooling at ambient temperature or under warming.

Preparation L: A process of (XXVII)→(XXVIII) [Process C]

THe compound (XXVIII) or a salt thereof can be prepared by halogenatingthe compound (XXVII) or a salt thereof.

The present halogenation can be carried out by using a conventionalhalogenating agent such as phosphorus trihalide, phosphorus pentahalide,phsophorus oxychloride, thionyl halide and the like.

The present reaction may be carried out in the presence of a base suchas lutidine, pyridine and the like.

The reaction is usually carried out in a solvent such as methylenechloride or any other solvents which do not adversely affect thereaction.

The reaction temperature is not critical and the reaction is preferablycarried out under cooling, at ambient temperature of under warming.

Preparation M: A process of (XXVIII)→(XXIX) [Process C]

The compound (XXIX) or a salt thereof can be prepared by reacting thecompound (XXVIII) or a salt thereof with a compound of the formula:##STR10## wherein R⁴ and R⁵ are each as defined above.

In case that ##STR11## is used in the present reaction, the presentreaction is preferably carried out in the presence of an base anaforementioned.

The reaction is usually carried out in a solvent such as methylenechloride, benzene or any other solvents which do not adversely affectthe reaction.

The reaction temperature is not critical and the reaction is preferablycarried out at ambient temperature or under warming.

Preparation N: A process of (III)→(II) [Process C]

The compound (II) or a salt thereof can be prepared by oxidizing thecompound (III) or a salt thereof.

The present reaction can be carried out substantially in the same methodas illustrated in Process 2.

The object compound (I) of the present invention exhibits highantimicrobial activity and inhibits the growth of a wide variety ofmicroorganisms including fungus.

For therapeutic administration, the cephalosporin analogues according tothe present invention are used in the form of pharmaceutical preparationwhich contain said compounds in admixture with a pharmaceuticallyacceptable carriers such as an organic or inorganic solid or liquidexcipient suitable for oral, parenteral or external administration. Thepharmaceutical preparations may be in solid form such as capsule,tablet, dragee, ointment or suppository, or in liquid form such assolution, suspension, or emulsion. If desired, there may be included inthe above preparations auxiliary substances, stabilizing agents, wettingor emulsifying agents, buffers and other commonly used additives.

While the dosage of the compounds may vary from and also depend upon theage and condition of the patient, an average single dose of about 50mg., 100 mg., 250 mg., and 500 mg. of the compounds according to thepresent invention has proved to be effective for treating of infectiousdiseases caused by a number of pathogenic bacteria. In general amountsbetween 1 mg. and about 1000 mg. or even more may be administered perday.

Now, in order to show the utility of the object compound (I), the testdata on anti-microbial activity of a representative compound of thepresent invention are shown below.

Test compound

(1) Benzyl 7β-(2-phenoxyacetamido)-2-oxo-3-cephem-4-carboxylate.

(2) Benzyl7β-(2-phenoxyacetamido)-1-oxodethia-2-oxo-3-cephem-4-carboxylate.

Test method

In vitro antibacterial activity was determined by the two-foldagar-plate dilution method as described below.

One loopful of an overnight culture of each test strain inTrypticase-soy broth (10⁴⁻⁵ viable spores per ml) was streaked on heartinfusion agar (HI-agar) containing graded concentrations of antibiotics,and the minimal inhibitory concentration (MIC) was expressed in terms ofμg/ml after incubation at 37° C. for 20 hours.

Test result

    ______________________________________                                                       MIC (μg/ml)                                                                Test Compound                                                  Test Bacteria    (1)     (2)                                                  ______________________________________                                        T. asteroides    100     200                                                  ______________________________________                                    

The following examples are given for the purpose of illustrating thepresent invention:-

EXAMPLE 1

Preparation of the starting compound:

(a)-(1) Triethylamine (31.2 ml.) was added at -40° C. to a solution ofbenzyl2-[2-oxo-3β-amino-4β-(methylthio)-azetidin-1-yl]-3-methyl-2-butenoatep-toluenesulfonate (49.2 g.) in methylene chloride (100 ml.), and then asolution of (2-acetoxyacetyl) chloride (15.3 g.) in methylene chloride(10 ml.) was added dropwise thereto over 30 minutes. Methylene chloride(25 ml.) was added thereto and the mixture was stirred for 40 minutes,during which the reaction temperature was gradually elevated to -7° C.Cold water and 1 N hydrochloric acid were added to the reaction mixture,and both the aqueous layer and the methylene chloride layer wereseparated. The aqueous layer was further extracted with methylenechloride. The extract and the methylene chloride layer separated abovewere combined together, in turn washed with 1 N hydrochloric acid, asaturated aqueous solution of sodium bicarbonate and an aqueous solutionof sodium chloride, dried over magnesium sulfate and concentrated togive oil of benzyl2-[2-oxo-3β-(2-acetoxyacetamido)-4β-(methylthio)azetidin-1-yl]-3-methyl-2-butenoate(43.95 g.)

I.R. (CH₂ Cl₂) 3410, 1770, 1720, 1695 cm⁻¹.

N.M.R. (CDCl₃, δ) 1.92 (3H, s), 1.99 (3H, s), 2.12 (3H, s), 2.24 (3H,s), 4.60 (2H, s), 5.04 (1H, d, J=4.5 Hz), 5.08 and 5.28 (2H, ABq, J=12Hz), 5.47 (1H, dd, J=4.5, 8 Hz), 7.03 (1H, d, J=8 Hz), 7.37 (5H, s).

(a)-(2) 1 N Aqueous solution of sodium hydroxide (100 ml.) was addeddropwise over 30 minutes at 3° C. to a solution of benzyl2-[2-oxo-3β-(2-acetoxyacetamido)-4β-(methylthio)azetidin-1-yl]-3-methyl-2-butenoate(43.95 g.) in a mixture of acetone (260 ml.) and water (100 ml.). Afterstirring for 10 minutes at the same temperature, the reaction mixturewas adjusted to pH 7 with 1 N hydrochloric acid and acetone wasdistilled off therefrom under reduced pressure. The mixture wasextracted twice with ethyl acetate (250 ml. and 50 ml.). The extractswere washed with a saturated aqueous solution of sodium bicarbonate andan aqueous solution of sodium chloride, dried over magnesium sulfate andconcentrated to give oil (38.8 g.). The oil was subjected to columnchromatography on silica gel (500 g.). The column was in turn elutedwith benzene (500 ml.×4), a mixture of benzene and acetone (17:3 ) and amixture of benzene and acetone (4:1).

Firstly, from the fractions of a mixture of benzene and acetone (17:3),the starting compound (6.10 g.) was recovered. And then, from thesubsequent fractions, benzyl2-[2-oxo-3β-(2-hydroxyacetamido)-4β-(methylthio)azetidin-1-yl]-3-methyl-2-butenoate(28.75 g.) was obtained.

I.R. (CH₂ Cl₂) 3600, 3400, 1770, 1720, 1690 cm⁻¹.

N.M.R. (CDCl₃, δ) 1.92 (3H, s), 2.03 (3H, s), 2.24 (3H, s), 4.12 (2H,s), 4.35 (1H, broad s), 5.14 (1H, d, J=4.5 Hz), 5.40 (1H, dd, J=4.5, 8Hz), 5.14 and 5.32 (2H, ABq, J=12 Hz), 7.36 (5H, s), 7.84 (1H, d, J=8Hz).

(a)-(3) Pyridine (7.35 ml.) was added at -30° C. to a solution of benzyl2-[2-oxo-3β-(2-hydroxyacetamido)-4β-(methylthio)azetidin-1-yl]-3-methyl-2-butenoate(28.65 g.) in methylene chloride (150 ml.), and then a solution of2,2,2-trichloroethyl chloroformate (17.7 g.) in methylene chloride (10ml.) was added dropwise thereto at -30° C. over 25 minutes. The reactiontemperature was elevated to 0° C., 1 N hydrochloric acid was addedthereto and the mixture was shaken. The methylene chloride layer wasseparated and the aqueous layer was further extracted with methylenechloride. The extracts were combined together, in turn washed with 1 Nhydrochloric acid, a saturated aqueous solution of sodium bicarbonateand an aqueous solution of sodium chloride, dried over magnesium sulfateand concentrated to give benzyl2-[2-oxo-3β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetamido}-4β-(methylthio)-azetidin-1-yl]-3-methyl-2-butenoate(43.30 g.).

I. R. (CH₂ Cl₂) 3400, 1770, 1710, 1695 cm⁻¹

N.M.R. (CDCl₃, δ) 1.92 (3H, s), 2.02 (3H, s), 2.27 (3H, s), 4.76 (2H,s), 4.82 (2H, s), 5.44 (1H, dd, J=4.5, 8 Hz), 5.04-5.32 (3H, m), 7.13(1H, d, J=8 Hz), 7.38 (5H, s)

(a)-(4) A solution of 2-(2,2,2-trichloroethoxycarbonyloxy)acetylchloride (114.2 g.) in methylene chloride (100 ml.) was added dropwiseto a solution of benzyl2-[2-oxo-3β-amino-4β-(methylthio)azetidin-1-yl]-3-methyl-2-butenoatep-toluenesulfonate (150 g.) in methylene chloride (1000 ml.) at -40° C.over a period of 30 minutes. The mixture was allowed to warm to 0° C.over a period of 30 minutes. The reaction mixture was washedsuccessively with 1 N hydrochloric acid, ice-water, a saturated aqueoussolution of sodium bicarbonate and a saturated aqueous solution ofsodium chloride, dried over magnesium sulfate and then evaporated. Theresidue was chromatographed on silica gel (1 kg.) and elutedsuccessively with benzene and a mixture of benzene and ethyl acetate(5:1 and 3:1) to give an oil of benzyl2-[2-oxo-3β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetamido}-4β-(methylthio)azetidin-1-yl]-3-methyl-2-butenoate(174.6 g.).

(a)-(5) A solution of chlorine (6.7 g.) in catoon tetrachloride (78 ml.)was at a time added at -70° C. to a solution of benzyl2-[2-oxo-3β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetamido}-4β-(methylthio)-azetidin-1-yl]-3-methyl-2-butenoate(43.30 g.) in methylene chloride (220 ml.) and the resulting mixture wasstirred for 17 minutes under -50° C. and then stirred for 34 minutes,during which the reaction temperature was gradually elevated to ambienttemperature. Nitrogen gas was passed into the reaction mixture underice-cooling for 40 minutes, and the mixture was concentrated to give oilof benzyl2-[2-oxo-3β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetamido}-4α-(chloro)azetidin-1-yl]-3-methyl-2-butenoate(51.5 g.) which contains a small amount of the corresponding 4β-chlorocompound.

I.R. (CH₂ Cl₂) 3400, 1780, 1710, 1695 cm⁻¹.

N.M.R. (CDCl₃ δ). 2.05 (3H, s), 2.34 (3H, s), 4.73 (2H, s), 4.84 (2H,s), 5.15 (1H, dd, J=2, 8 Hz), 5.20 (2H, broad s), 5.80 (1H, d, J=2 Hz),7.3 (1H, d, J=8 Hz), 7.40 (5H, s).

(a)-(6) To a solution of benzyl2-[2-oxo-3β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetamido}-4α-(chloro)azetidin-1-yl]-3-methyl-2-butenoatewhich contains a small amount of the corresponding 4β-chloro compound(2.37 g.) in methylene chloride (20 ml.) were in turn added silver oxide(0.65 g.) and silver tetrafluoroborate (1.10 g) and the resultingmixture was stirred at -20° C. After stirring for 1 hour, methylenechloride (10 ml.) was added thereto. After stirring for additional 30minutes, the reaction mixture was allowed to warm to 0° C. and thenbenzene (30 ml.) and sodium chloride (1 g) were added thereto. Afterstirring for 15 minutes, to the mixture was added a saturated aqueoussolution of sodium chloride (3 ml.) and the stirring was continued for10 minutes. The resulting mixture was filtered and the organic layer inthe filtrate was in turn washed with a saturated aqueous solution ofsodium chloride, water and a saturated aqueous solution of sodiumchloride, dried and concentrated to give an oil (2.30 g.). The oil waschromatographed on silica gel (60 g.) and eluted with methylene chlorideand then a mixture of methanol and methylene chloride (1:199) to givecolorless oil of benzyl2-[2-{(2,2,2-trichloroethoxy)carbonyloxymethyl}-4-oxo-3a,5a-dihydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(1.47 g.), which has the following structural formula. ##STR12##

I. R. (CH₂ Cl₂) 1780, 1720 cm⁻¹.

N.M.R. (CDCl₃, δ) 1.91 (3H, s), 2.25 (3H, s), 4.73 (2H, s), 4.75 (2H,s), 5.11 and 5.22 (2H, ABq, J=13 Hz), 5.2 (1H), 5.98 (1H, d, J=4 Hz),7.32 (5H, s).

(a)-(7) To a solution of benzyl2-[2-{(2,2,2-trichloroethoxy)carbonyloxymethyl}-4-oxo-3a,5a-dihydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(680 mg.) in anhydrous tetrahydrofuran (5 ml.) were added at -78° C.pyridine (0.15 ml.) and 2-phenoxyacetyl chloride (0.21 ml.). Theresulting mixture was allowed to warm to ambient temperature withstirring. After stirring for 12/3 hours, the reaction mixture wasconcentrated at ambient temperature and the residue was extracted withethyl acetate. The extract was washed in turn with a dilutedhydrochloric acid, a diluted aqueous solution of sodium chloride(twice), a diluted aqueous solution of sodium bicarbonate, a dilutedaqueous solution of sodium chloride and a saturated aqueous solution ofsodium chloride, dried over magnesium sulfate and concentrated to givean oil of benzyl2-[2-{(2,2,2-trichloroethoxy)carbonyloxymethylene)-3-(phenoxyacetyl)-4-oxo-2,3,3a,5a-tetrahydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(880 mg.), which has the following structural formula. ##STR13##

I.R. (CH₂ Cl₂) 1785, 1725, 1700, 1600 cm⁻¹.

N.M.R. (CDCl₃, δ) 1.97 (3H, s), 2.32 (3H, s), 4.82 (2H, s), 4.92 (2H,broad d, J=2 Hz), 5.22 (2H, broad d, J=2 Hz), 5.58 (1H, d, J=4 Hz), 6.15(1H, d, J=4 Hz), 6.8-7.6 (10H, m), 7.67 (1H, s).

(a)-(8) A mixture of benzyl2-[2-{2,2,2-trichloroethoxy)carbonyloxymethylene}-3-(2-phenoxyacetyl)-4-oxo-2,3,3a,5a-tetrahydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(1.30 g.), d-camphorsulfonic acid (23 mg.), methylene chloride (15 ml.)and water (0.054 ml.) was stirred for 30 minutes at ambient temperature.The mixture was extracted with ethyl acetate. The extract was in turnwashed with an aqueous solution of sodium bicarbonate, water and asaturated aqueous solution of sodium chloride, dried and concentrated togive an oil (1.37 g.). The oil was chromatographed on silica gel (20 g.)and eluted with a mixture of benzene and acetone (9:1) to give an oil ofbenzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetoxy}azetidin-1-yl]-3-methyl-2-butenoate(1.08 g.).

I.R. (CH₂ Cl₂) 1780, 1765, 1720, 1695 cm⁻¹.

N.M.R. (CDCl₃, δ) 2.08 (3H, s), 2.30 (3H, s), 4.5-4.9 (6H, m), 5.23 (2H,s), 5.38 (1H, dd, J=4, 8 Hz), 6.38 (1H, d, J=4 Hz), 6.8-7.6 (11H, m)

(a)-(9) To a solution of benzyl2-[2-{(2,2-trichloroethoxy)carbonyloxymethyl}-4-oxo-3a,5a-dihydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(15.0 g.) in dry acetone (100 ml.) was added p-toluenesulfonic acidmonohydrate (5.81 g.) and the resulting solution was stirred for 20minutes at 18° C. The reaction mixture was concentrated under reducedpressure to give a semisolid (23 g.). The residue was triturated withdiethyl ether (50 ml.) and then petroleum ether (70 ml.) was addedthereto. The mixture was cooled, and precipitates were collected byfiltration and dried under reduced pressure to give white powder ofbenzyl2-[2-oxo-3β-amino-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]-3-methyl-2-butenoatep-toluenesulfonate (18.1 g.), m.p. 109°-113° C. (dec.)

I.R. (CH₂ Cl₂) 1785, 1770, 1725 cm⁻¹.

N.M.R. (d₆ -DMSO, δ) 2.00 (3H, s), 2.18 (3H, s), 2.33 (3H, s), 4.8-5.1(3H, m), 5.01 (2H, s), 5.25 (2H, s), 6.47 (1H, d, J=4 Hz), 7.17 and 7.55(4H, ABq, J=8 Hz), 7.42 (5H, s)

(a)-(10) To a suspension of benzyl2-[2-oxo-3β-amino-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]-3-methyl-2-butenoatep-toluenesulfonate (4.0 g.) in dry methylene chloride (20 ml.) was added2-phenoxyacetyl chloride (1.03 ml.) under ice-cooling, and to themixture was added dropwise a solution of pyridine (1 ml.) in drymethylene chloride (4 ml.). The mixture was stirred for 30 minutes atthe same temperature, and then evaporated under reduced pressure. Theresulting residue was dissolved in ethyl acetate (100 ml.) and in turnwashed with dilute hydrochloric acid, water, aqueous solution of sodiumbicarbonate and aqueous solution of sodium chloride, and then evaporatedto to give oil of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}-azetidin-1-yl]-3-methyl-2-butenoate(3.9 g.).

(a)-(11) A mixture of Ozone and Oxygen gas was passed at -78° C. into asolution of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]-3-methyl-2-butenoate(338 mg.) in ethyl acetate (6 ml.) until the color of the solution waschanged into blue, and the solution was allowed to stand for 5 minutesat -78° C. Then nitrogen gas was passed into the solution at -78° C. toremove an excess ozone gas. The resulting solution was poured into asolution of sodium bisulfite (1.04 g.) and sodium sulfite (0.32 g.) inwater (10 ml.) and extracted with ethyl acetate. The extract was in turnwashed twice with a diluted aqueous solution of sodium chloride and witha saturated aqueous solution of sodium chloride, dried and concentratedto give a foamy substance (350 mg.), which was crystallized by additionof a mixture of methanol and ether (1:9) to give crystals of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-l-yl]glyoxylate(240 mg.), m.p. 122°-126° C. (dec.)

I.R. (Nujol) 1830, 1765, 1740, 1720, 1680 cm⁻¹.

N.M.R. (CDCl₃, δ) 4.49 (4H, s), 4.57 (2H, s), 5.26 (2H, s), 5.47 (1H,dd, J=5,9 Hz), 6.70 (1H, d, J=5 Hz), 6.6-7.5 (11H, m).

(a)-(12) A mixture of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]glyoxylate(395 mg.), zinc powder (300 mg.), propionic acid (0.3 ml.) and methylenechloride (4 ml.) was stirred for 40 minutes at 0° C., for 10 minutes at13° C. and for 7 minutes at 0° C. The reaction mixture was diluted withcold ethyl acetate (4 ml.) and filtered. The filtrate was in turn washedwith a chilled sodium bicarbonate aqueous solution, a diluted aqueoussolution of sodium chloride and a saturated aqueous solution of sodiumchloride, dried over magnesium sulfate and evaporated to give a foamysubstance of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]glycolate(a mixture of epimer at 2 position) (370 mg.).

I.R. (CH₂ Cl₂) 1795, 1765, 1695 cm⁻¹.

(a)-(13) To a solution of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]glycolate(a mixture of epimer at 2 position) (1.26 g.) and 2,6-lutidine (0.35ml.) in methylene chloride (15 ml.) was added at -30° C. thionylchloride (0.22 ml.), and the resulting mixture was allowed to warm to 0°C. over 20 minutes and left at 0° C. for 12/3 hours. The reactionmixture was poured into a chilled diluted aqueous solution of sodiumchloride and extracted with ethyl acetate. The extract was successivelywashed with a diluted aqueous solution of sodium chloride, a dilutedaqueous solution of sodium bicarbonate and a saturated aqueous solutionof sodium chloride, dried and concentrated to give an oil of benzyl2-chloro-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy)azetidin-1-yl]-acetate(a mixture of epimer at 2 position) (1.31 g.)

I.R. (CH₂ Cl₂) 1805, 1765, 1730, 1700 cm⁻¹

(a)-(14) A mixture of the oil (1.31 g.) obtained in the above (10),triphenylphosphine (1.05 g.) and methylene chloride (10 ml.) was allowedto stand for 12 hours at ambient temperature and then heated underreflux for 4.5 hours. The reaction mixture was diluted with methylenechloride, washed with a diluted aqueous solution of sodium bicarbonate,dried over magnesium sulfate and evaporated to give a brown oil. The oilwas chromatographed on silica gel (12 g.) and successively eluted withbenzene, benzene:ethyl acetate (10:1) and benzene:ethyl acetate (4:1) togive an amorphous solid of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]acetate(986 mg.).

I.R. (CH₂ Cl₂) 1765, 1690, 1620 cm⁻¹.

(a)-(15) A mixture of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]acetate(915 mg.), zinc powder (750 mg.), acetic acid (0.5 ml.) and methylenechloride (5.0 ml.) was stirred for 4 hours at 15° C. Zinc powder (150mg.) was further added and the mixture was stirred for 1 hour at 15° C.The reaction mixture was filtered and the filtrate was in turn washedwith a saturated aqueous solution of sodium bicarbonate (16 ml.), water,and a saturated aqueous solution of sodium chloride, dried overmagnesium sulfate and evaporated to give an oil (780 mg.). The oil waschromatographed on silica gel (5 g.) and successively eluted withbenzene, benzene:ethyl acetate (10:1), benzene:ethyl acetate (5:1),benzene:ethyl acetate (2:1) and ethyl acetate to give a foamy substanceof benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-(2-hydroxyacetoxy)azetidin-1-yl]acetate(550 mg.).

I.R. (CH₂ Cl₂) 1780, 1755, 1690, 1620 cm⁻¹.

(b)-(1) To a solution of benzyl2-[2-oxo-3β-(2-acetoxyacetamido)-4β-(methylthio)azetidin-1-yl]-3-methyl-2-butenoate(4.4 g) in methylene chloride (50 ml) was added a solution of chlorine(1.5 g) in carbon tetrachloride (20 ml) at -78° C. The resultingsolution was stirred at -78° C. for 40 minutes and at 0° C. for 20minutes. The reaction mixture was poured into a cold aqueous solution ofsodium bicarbonate and then extracted with methylene chloride (100 ml,10 ml×2). The extracts were combined, washed successively with water anda saturated aqueous solution of sodium chloride, dried over magnesiumsulfate and then evaporated to give an oil of benzyl2-[2-oxo-3β-(2-acetoxyacetamido)-4α-(chloro)azetidin-1-yl]-3-methyl-2-butenoate(5.5 g).

I.R. (CH₂ Cl₂): 1780, 1755, 1700 cm⁻¹

N.M.R. (CDCl₃, δ): 2.00 (3H, s), 2.10 (3H, s), 2.27 (3H, s), 4.54 (2H,s), 5.04 (1H, d, J=8 Hz), 5.18 (2H, s), 5.76 (1H, s), 7.24 (5H, s).

(b)-(2) To a solution of benzyl2-[2-oxo-3β-(2-acetoxyacetamido)-4α-(chloro)azetidin-1-yl]-3-methyl-2-butenoate(5.5 g) in tetrahydrofuran (40 ml) were added silver oxide (4.6 g) andsilver tetrafluoroborate (3.90 g) at -30° C. The resulting mixture wasstirred at -20° to -10° C. for 2 hours and 40 minutes and at roomtemperature for one hour. The reaction mixture was cooled to 0° C. andthen benzene (100 ml), an aqueous solution of sodium chloride (20 ml),and an aqueous solution of sodium bicarbonate (20 ml) were addedthereto. The mixture was stirred for 20 minutes and filtered through apad of Celite. The organic layer was separated, washed wih a saturatedaqueous solution of sodium chloride (x3), dried over magnesium sulfateand then evaporated. The residual oil (5.4 g) was chromatographed onsilica gel (120 g) and eluted first with methylene chloride and thenwith 1.5% solution of methanol in methylene chloride to give an oil ofbenzyl2-[2-acetoxymethyl-4-oxo-3a,5a-dihydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(3.30 g), which has the following structural formula. ##STR14##

I.R. (CH₂ Cl₂): 1780, 1750, 1720 cm⁻¹

N.M.R. (CDCl₃, δ): 1.94 (3H, s), 2.12 (3H, s), 2.19 (3H, s), 4.69 (2H,s), 5.2 (1H), 5.23 (2H, s), 6.01 (1H, d, J=3 Hz), 7.38 (5H, s).

(b)-(3) A mixture of benzyl2-[2-acetoxymethyl-4-oxo-3a,5a-dihydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(985 mg) and potassium carbonate (440 mg) in acetone (15 ml) and water(7.5 ml) was heated at 55° C. for 3 hours. The resulting solution wasconcentrated and to the residue was added ethyl acetate. The ethylacetate layer was washed successively with water and a saturated aqueoussolution of sodium chloride, dried over magnesium sulfate and thenevaporated. The residual oil (800 ml) was chromatographed on silica gel(30 g) and eluted first with benzene and then with a mixture of benzeneand acetone (3:1) to give benzyl2-[2-hydroxymethyl-4-oxo-3a,5a-dihydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(210 mg) and the starting compound (322 mg) was also recovered. Theproduct was identified with that prepared in Example 1 (b)-(5) on aT.L.C. plate.

(b)-(4) To a solution of benzyl2-[2-oxo-3β-(2-hydroxyacetamido)-4β-(methylthio)azetidin-1-yl]-3-methyl-2-butenoate(1.15 g) in methylene chloride (20 ml) was added a solution of chlorine(440 mg) in carbon tetrachloride (2.5 ml) all at once at -78° C. Theresulting mixture was stirred at -78° C. for 40 minutes and at 0° C. for40 minutes. The reaction mixture was poured into a chilled aqueoussolution of sodium bicarbonate (50 ml) and then extracted with methylenechloride. The extracts were washed with a saturated aqueous solution ofsodium chloride, dried over magnesium sulfate and then evaporated togive an oil of benzyl2-[2-oxo-3β-(2-hydroxyacetamido)-4β-(chloro)azetidin-1-yl]-3-methyl-2-butenoate(1.35 g).

I.R. (CH₂ Cl₂): 1780, 1720, 1690 cm⁻¹

(b)-(5) To a mixture of benzyl2-[2-oxo-3β-(2-hydroxyacetamido)-4β-(chloro)azetidin-1-yl]-3-methyl-2-butenoate(380 mg) and silver oxide (400 mg) in anhydrous tetrahydrofuran (6 ml)was added silver tetrafluoroborate (320 mg) at -40° C. The resultingmixture was stirred at -40° to -30° C. for 30 minutes and then graduallywarmed to 0° C. After 70 minutes, benzene (20 ml), an aqueous solutionof sodium chloride (3 ml) and a saturated aqueous solution of sodiumbicarbonate (1 ml) were added thereto. The reaction mixture was stirredfor 5 minutes and then filtered through a pad of Celite. The filtratewas washed successively with water and a saturated aqueous solution ofsodium chloride, dried over magnesium sulfate and then evaporated togive an oil (300 mg). The oil (265 mg) was chromatographed on silica gel(7.5 g) and eluted first with methylene chloride and then with 2%solution of methanol in methylene chloride. Fractions containing theobject compound were collected and then evaporated to give benzyl2-[2-hydroxymethyl-4-oxo-3a,5a-dihydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(96 mg), which has the following structural formula. ##STR15##

I.R. (CH₂ Cl₂): 1780, 1720, 1655 cm⁻¹

N.M.R. (CDCl₃, δ): 1.90 (3H, s), 2.27 (3H, s), 3.9 (1H, m), 4.24 (2H,broad s), 5.20 (1H, d, J=3 Hz), 5.23 (2H, s), 6.03 (1H, d, J=3 Hz), 7.39(5H, s).

(b)-(6) To a solution of benzyl2-[2-hydroxymethyl-4-oxo-3a,5a-dihydro-4H-azeto[3,2-d]oxazol-5-yl]-3-methyl-2-butenoate(210 mg) and pyridine (64 ml) in methylene chloride (4.5 ml) was addedat -35° C. 2,2,2-trichloroethyl chloroformate (96 μl). The resultingmixture was gradually allowed to warm to 0° C. over a period of onehour. The reaction mixture was diluted with ethyl acetate, washedsuccessively with dil. hydrochloric acid, water, a saturated aqueoussolution of sodium chloride, a dil. aqueous solution of sodiumbicarbonate, a dil. aqueous solution of sodium chloride and a saturatedaqueous solution of sodium chloride. The organic layer was dried overmagnesium sulfate and evaporated. The residual oil (311 mg) waschromatographed on silica gel (10 g) and eluted with methylene chlorideto give an oil of benzyl2-[2-{(2,2,2-trichloroethoxy)carbonyloxymethyl}-4-oxo-3a,5a-dihydro-4H-azeto[3,2-d]-oxazol-5-yl]-3-methyl-2-butenoate(200 mg). The product was identified with that prepared in Example 1 (a)(6) on a T.L.C. plate.

Preparation of the starting compound

(c)-(1) To a suspension of benzyl2-[2-oxo-3β-amino-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]-3-methyl-2-butenoatep-toluenesulfonate (18.1 g.) and benzyl chloroformate (3.82 ml.) inmethylene chloride (80 ml.) was added dropwise at 0° C. over 15 minutesa solution of pyridine (4.90 ml.) in methylene chloride (10 ml.). Themixture was stirred for 1 hour at 0° C. and concentrated. The residuewas dissolved in ethyl acetate (250 ml.), and the solution was in turnwashed twice with diluted hydrochloric acid, water, diluted aqueoussolution of sodium bicarbonate and a saturated aqueous solution ofsodium chloride, dried over magnesium sulfate and concentrated to givean oil (13.2 g.). The oil was chromatographed on silica gel (220 g.) andeluted with benzene and benzene-acetone (20:3) to give an oil of benzyl2-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]-3-methyl-2-butenoate (13.2 g.).

I.R. (CH₂ Cl₂) 1780, 1760, 1720 cm⁻¹.

N.M.R. (CDCl₃, δ) 2.00 (3H, s), 2.26 (3H, s), 4.60 (2H, s) 4.76 (2H, s),5.16 (2H, s), 5.20 (2H, s), 5.25 (1H), 5.47 (1H, broad d, J=9 Hz), 6.34(1H, d, J=4 Hz), 7.37 (10H, s).

(c)-(2) To a solution of benzyl2-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetoxy}azetidin-1-yl]-3-methyl-2-butenoate(13.7 g.) in ethyl acetate (260 ml.) was passed at -78° C. a stream ofoxygen containing ozone gas for 20 minutes. After the color of thesolution became pale blue, an excess ozone gas was removed by bubblingnitrogen gas into the solution at -78° C. for 15 minutes. The mixturewas gradually warmed to 0° C. over 40 minutes under a stream ofnitrogen. The resulting mixture was poured into a chilled solution ofsodium sulfite (10.4 g.) and sodium bisulfite (3.2 g.) in water (100ml.), and the mixture was shaken. The organic layer was separated,washed with a diluted aqueous solution of sodium chloride (50 ml.) and asaturated aqueous solution of sodium chloride, dried over magnesiumsulfate and evaporated to dryness to give an amorphous solid. Theresidue was crystallized by adding diethyl ether (30 ml.) and themixture was evaporated to dryness. To the residue was added diisopropylether (50 ml.) and the residue was triturated. Crystals were collectedby filtration, washed with diisopropyl ether (25 ml.×2) and dried invacuo to give benzyl2-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]glyoxylate(12.07 g.), m.p. 118°-121° C. (dec.).

I.R. (Nujol) 1830, 1765, 1735, 1720, 1698 cm⁻¹.

N.M.R. (CDCl₃,δ) 4.56 (2H, broad s), 4.74 (2H, s), 5.10 (2H, broad s),5.30 (2H, s), 5.2-5.4 (1H, m), 5.68 (1H, d, J=9 Hz), 6.69 (1H, d, J=4Hz), 7.32 (5H, s), 7.38 (5H, s).

(c)-(3) Zinc powder (995 mg.) was added at 13° C. to a solution ofbenzyl2-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]glyoxylate(4.80 g.) and acetic acid (4.8 ml.) in methylene chloride (40 ml.). Theresulting mixture was stirred for 3 hours at 13° to 17° C. under astream of nitrogen, during which an additional zinc powder (400 mg.) wasadded to the mixture in four portions. The reaction mixture was dilutedwith ethyl acetate (50 ml.) and filtered. The filtrate was diluted withethyl acetate (150 ml.), in turn washed with cold water, a dilutedaqueous solution of sodium bicarbonate and an aqueous solution of sodiumchloride, dried over magnesium sulfate and concentrated to give an oilof benzyl2-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]-glycolate(a mixture of epimers at 2 position (4.60 g.). The oil waschromatographed on silica gel and eluted with a mixture of benzene andethyl acetate (4:1) to give a pure compound.

I.R. (CH₂ Cl₂) 1800, 1765, 1740 cm⁻¹

N.M.R. (CDCl₃,δ) 4.52 and 4.63 (2H, two s), 4.75 (2H, s), 5.12 (2H, s),5.22 and 5.25 (2H, two s), 5.1-5.6 (2H, m), 5.65-6.0 (1H, m), 6.17 and6.33 (1H, two d), 7.37 (10H, broad s)

(c)-(4) To a solution of benzyl2-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetoxy)azetidin-1-yl]glycolate(9.30 g.) and 2,6-dimethylpyridine (2.68 ml.) in methylene chloride (100ml.) was added dropwise thionyl chloride (1.68 ml.) over a period of 5minutes at -30° C. under a nitrogen atmosphere. The resulting mixturewas allowed to warm to 0° C. over a period of 20 minutes and thenstirred at 0° C. for 1.5 hours. The reaction mixture was poured intoice-water (40 ml.) and thereto was added methylene chloride (50 ml.).After the resulting mixture was shaken, the methylene chloride layer wasseparated therefrom. The methylene chloride layer was washedsuccessively with ice water and an ice-cooled mixture of a saturatedaqueous solution of sodium chloride (50 ml.) and a saturated aqueoussolution of sodium bicarbonate (15 ml.), dried over magnesium sulfateand then evaporated to give an oil of benzyl 2-chloro-2-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetoxy}azetidin-1-yl]acetate(a mixture of epimers at 2 position) (9.50 g.).

I.R. (CH₂ Cl₂) 1805, 1770, 1735 cm⁻¹.

(c)-(5) A solution of benzyl2-chloro-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetoxy}azetidin-1-yl]acetate(9.50 g.) and triphenylphosphine (7.9 g.) in methylene chloride (70 ml.)was allowed to stand at room temperature for 13.5 hours under a nitrogenatmosphere and then refluxed under heating for 7 hours also under anitrogen atmosphere. The reaction mixture was concentrated and pouredinto ethyl acetate (150 ml.) The mixture was washed successively with anice-cooled saturated aqueous solution of sodium bicarbonate (30 ml.) anda saturated aqueous solution of sodium chloride, dried over magnesiumsulfate and then evaporated. The obtained residual oil (16.4 g.) wassubjected to column chromatography on silica gel (200 g.) and elutedsuccessively with benzene and a mixture of benzene and acetone (themixing ratio: 7/1, 5/1, 4/1, 3/1 and then 2/1). The fractions containingthe desired compound were evaporated to give an oil of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetoxy}azetidin-1-yl]acetate (6.80g.).

I.R. (CH₂ Cl₂) 1775, 1770, 1725, 1625 cm⁻¹.

(c)-(6) To a solution of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-benzyloxycarboxamido-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetoxy}azetidin-1-yl]acetate(6.75 g.) in a mixture of methylene chloride (35 ml.) and acetic acid(3.5 ml.) was added zinc powder (5.5 g.) with stirring at 15° C., andthe resulting mixture was stirred at the same temperature for anadditional 2 hours and allowed to stand at 0° C. for an hour. Thereaction mixture was diluted with ethyl acetate (40 ml.), filtered, andthe solid was washed with ethyl acetate. The combined ethyl acetatefiltrate and washing was shaked with an ice-cooled saturated aqueoussolution of sodium bicarbonate (100 ml.) and then filtered. The organiclayer was separated and the remaining aqueous layer was extracted withethyl acetate (50 ml.). The separated organic layer and the extract werecombined together, washed successively with water and a saturatedaqueous solution of sodium chloride, dried over magnesium sulfate andthen filtered. The filtrate was evaporated to give an amorphous solid(5.35 g.). Thus obtained solid was chromatographed on silica gel (35 g.)and eluted successively with benzene and a mixture of benzene and ethylacetate (the mixing ratio: 5/1, 2/1 and then 1/1). The fractionscontaining the desired compounds were evaporated to give an amorphoussolid of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-benzyloxycarboxamido-4β-(2-hydroxyacetoxy)azetidin-1-acetate (4.11 g.).

I.R. (CH₂ Cl₂) 1780, 1750, 1725, 1620 cm⁻¹.

Preparation of the object compound:

(d)-(1) A mixture of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-(2-hydroxyacetoxy)-azetidin-1-yl]acetate(288 mg.), dimethylsulfoxide (1.4 ml.) and acetic anhydride (1.4 ml.)was stirred for 4 hours at ambient temperature. In the course of thereaction, benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-(glyoxyloyloxy)azetidin-1-yl]-acetatewas produced. The reaction mixture was concentrated under reducedpressure at ambient temperature to a volume of 1.5 ml. The residue waspoured into a chilled, diluted sodium bicarbonate aqueous solution andextracted with a mixture of benzene and ethyl acetate (1:2). The extractwas successively washed with a diluted aqueous solution of sodiumchloride, water (3 times) and a saturated aqueous solution of sodiumchloride, dried over magnesium sulfate and evaporated to give an oil(282 mg.). The oil was chromatographed on silica gel (5 g.) and elutedwith benzene and acetone (5:1) to give an amorphous solid of benzyl7β-(2-phenoxyacetamido)- 1-oxadethia-2-oxo-3-cephem-4-carboxylate (134mg.).

I.R. (CH₂ Cl₂) 1820, 1745, 1700 cm⁻¹.

N.M.R. (CDCl₃, δ) 4.53 (2H, s), 5.33 (2H, s), 5.77 (2H, m), 6.18 (1H,s), 6.7-7.7 (11H, m).

(d)-(2) A solution of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-benzyloxycarboxamido-4β-(2-hydroxyacetoxy)azetidin-1-yl]acetate(1.00 g.) in a mixture of dimethylsulfoxide (4 ml.) and acetic anhydride(4 ml.) was stirred at room temperature for 5 hours and 40 minutes, andthen further stirred at 28° to 31° C. for 70 minutes. In the course ofthe reaction, benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-benzyloxycarboxamido-4β-(glyoxyloyloxy)-azetidin-1-yl]acetatewas produced. The reaction mixture was concentrated to the volume ofabout 4 ml under reduced pressure at room temperature. The concentratewas dissolved in a mixture of ethyl acetate and benzene (1:1) (80 ml.),and washed successively with a chilled diluted aqueous solution ofsodium bicarbonate, a saturated aqueous solution of sodium chloride,water (3 times) and a saturated aqueous solution of sodium chloride. Thesolution was dried and then evaporated to give a yellow oil (1.06 g.).Thus obtained oil was chromatographed on silica gel (15 g.) and elutedwith a mixture of benzene and ethyl acetate (4:1). The fractionscontaining the object compound were evaporated to give an oil of benzyl7β-benzyloxycarboxamido-1-oxadethia-2-oxo-3-cephem-4-carboxylate (370mg.).

I.R. (CH₂ Cl₂) 1818, 1735 cm⁻¹.

N.M.R. (acetone-d₆,δ) 5.11 (2H, s), 5.35 (2H, s), 5.66 (1H, dd, J=4,9Hz), 6.06 (1H, d, J=4 Hz), 6.31 (1H, s), 7.1-7.6 (10H, m).

EXAMPLE 2

The following compounds were prepared in the similar manner to thatdescribed in Example 1.

(1) Benzyl7β-[2-pentyloxyimino-2-(2-formamidothiazol-4-yl)acetamido]-1-oxadethia-2-oxo-3-cephem-4-carboxylate(syn isomer).

I.R. (CH₂ Cl₂): 3350, 1810, 1730, 1690 cm⁻¹

(2) Benzyl7β-(2-methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylate(syn isomer).

I.R. (CH₂ Cl₂): 3390, 1815, 1740, 1685, 1610 cm⁻¹.

N.M.R. ((CD₃)₂ C=0,δ): 3.95 (3H, s), 5.40 (2H, s), 6.03 (1H, dd, J=4,8Hz), 6.23 (1H, d, J=4 Hz), 7.33-7.83 (10-11H, m).

EXAMPLE 3 Preparation of the starting compounds

(a)-(1) To a suspension of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β(mercapto)azetidin-1-yl]-3-methyl-3-butenoate(4.40 g) and 2-(2,2,2-trichloroethoxycarbonyloxy)acetyl chloride (4.02g) in absolute methylene chloride (22 ml) was added a solution ofpyridine (1.03 g) in methylene chloride (5 ml) at -15° to -10° C. withstirring and the stirring was continued for 15 minutes. The reactionmixture was poured into a mixture of ethyl acetate (100 ml) and 2%hydrochloric acid (30 ml). The organic layer was separated, washedsuccessively with water (x2), 5% aqueous solution of sodium bicarbonate(x2) and an aqueous solution of sodium chloride (x3) and then evaporatedto give benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetylthio}azetidin-1-yl]-3-methyl-3-butenoate(8.0 g).

I.R. (CH₂ Cl₂): 1750, 1720, 1700 cm⁻¹.

N.M.R. (CDCl₃,δ): 1.85 (3H, s), 4.5-5.3 (7H, m), 5.47 (1H, dd, J=5 and 8Hz), 6.10 (1H, d, J=5 Hz), 6.8-7.5 (11H, m)

(a)-(2) Benzyl2-[2-Oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2,-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]-3-methyl-3-butenoate(520 mg) was dissolved in ethyl acetate (15 ml) and ozonized undercooling with dry ice-acetone bath until the solution turned pale blue.After the solution was allowed to stand for 10 minutes at the sametemperature, nitrogen gas was bubbled through the solution and then thetemperature was raised to room temperature. The resulting solution waswashed with a solution of sodium sulfite (15 g) and sodium bisulfite (50g) in water (500 ml) and the washings were extracted with ethyl acetate.The washed organic layer and ethyl acetate extract were combined, washedwith a saturated aqueous solution of sodium chloride, dried overmagnesium sulfate and then evaporated to give an oil of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]-3-hydroxy-2-butenoate(533 mg).

I.R. (CH₂ Cl₂): 3400, 1775, 1700, 1660 cm⁻¹.

N.M.R. (CDCl₃,δ): 2.24 (3H, s), 4.56 (2H, s), 4.77 (2H, s), 4.80 (2H,s), 5.25 (2H, s), 5.21 (1H, d,d, J=5 and 9 Hz), 6.00 (1H, d, J=5 Hz),6.86-7.50 (10H, m).

(a)-(3) Benzyl2-[2-Oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}-azetidin-1-yl]-3-hydroxy-2-butenoate(244 mg) was dissolved in ethyl acetate (15 ml) and ozonized undercooling with dry ice-acetone until the blue color turned dark. Nitrogengas was bubbled through the solution and then the temperature was raisedto room temperature. The resulting solution was washed with a sodiumsulfite-sodium bisulfite solution and then the washing was extractedwith ethyl acetate. The washed organic layer and ethyl acetate extractwere combined, washed with an aqueous solution of sodium chloride, driedover magnesium sulfate and then evaporated. Diethyl ether and seeds ofthe object compound were added to the residue and the crystals werecollected by filtration washed with diethyl ether and thenrecrystallized from a mixture of ethyl acetate and diethyl ether to givebenzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxycarbonyloxy)acetylthio}azetidin-1-yl]glyoxylate(140 mg), mp 130°-134° C.

I.R. (Nujol): 3350, 1820, 1760, 1730, 1720, 1660 cm⁻¹.

N.M.R. (CDCl₃,δ): 4.56 (2H, s), 4.74 (4H, s), 5.33 (2H, s), 5.50 (1H,dd, J=6.5 and 8.5 Hz), 6.05 (1H, d, J=8.5 Hz), 6.8-7.4 (10H, m).

    ______________________________________                                        Elemental Analysis                                                            C              H      N          S    Cl                                      ______________________________________                                        Calc'd: 46.35      3.27   4.32     4.95 16.42                                 Found:  45.95      3.16   4.35     5.27 16.46                                 ______________________________________                                    

(a)-(4) To a solution of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]-3-methyl-3-butenoate(20.5 g) in benzene (200 ml) was added triethylamine (0.85 ml) underice-cooling. The mixture was stirred for 70 minutes at room temperature.The reaction mixture was washed successively with 1 N hydrochloric acid(60 ml×2) and an aqueous solution of sodium chloride, dried overmagnesium sulfate and then evaporated. The residue was subjected tocolumn chromatography on silica gel (120 g), using a mixture of benzeneand ethyl acetate (40:1 to 30:1). The fractions containing the objectcompound were combined and evaporated to give an oil of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]-3-methyl-2-butenoate(6.2 g).

I.R. (CH₂ Cl₂): 3400, 1770, 1720, 1700 cm⁻¹

N.M.R. (CDCl₃,δ): 2.07 (3H, s), 2.25 (3H, s), 4.55 (2H, s), 4.72 (2H,s), 4.75 (2H,s), 5.21 (2H, s), 5.14 (1H, m), 6.01 (1H, d, J=5 Hz),6.85-7.41 (10H, m).

(a)-(5) Benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxyacetylthio}azetidin-1-yl]-3-methyl-2-butenoate(11.8 g) was dissolved in ethyl acetate (130 ml) and ozonized undercooling with dry ice-acetone bath until the solution turned blue.Nitrogen gas was bubbled through the solution. The resulting solutionwas washed successively with 50 ml (×2) portions of a solution of sodiumbisulfite (50 g) and sodium sulfite (15 g) in water (500 g) and anaqueous solution of sodium chloride, dried over magnesium sulfate andthen evaporated to give an oil of benzyl2-[2-oxo-3β-(2-phenoxyactamido)-4β-{2-2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]glyoxylate(10.9 g). This product was identified with that obtained in Example 2(a)-(3).

(a)-(6) To a suspension of aluminum amalgam (prepared from aluminumpowder (20 g) by usual manner) in tetrahydrofuran (300 ml) was addedbenzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]glyoxylate(19.9 g). After the mixture was cooled to 6°-7° C., acetic acid (20 ml)and water (6 ml) were added. The resulting mixture was stirred for 70minutes at the same temperature and filtered through a pad of Celite.The filtrate was concentrated to half volume and poured into ethylacetate (700 ml). The mixture was washed with a solution of sodiumbicarbonate (44 g) in water (500 ml) and the washing was extracted withethyl acetate. The organic layers were combined, washed with an aqueoussolution of sodium chloride and dried over magnesium sulfate and thenevaporated to give a foam of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]glycolate(a mixture of epimers at 2 position)(18.8 g).

I.R. (CH₂ Cl₂): 3480, 3380, 1780, 1740 1690 cm⁻¹.

(a)-(7) To a mixture of acetic acid (0.5 ml) and methylene chloride (10ml) were added successively benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]glyoxylate(520 mg) and zinc powder (410 mg) with stirring. After the resultingmixture was stirred for an hour at room temperature, insolublesubstances were filtered off. The filtrate was diluted with ethylacetate (50 ml), washed with a dil. aqueous solution of sodiumbicarbonate and sodium chloride, dried over magnesium sulfate and thenevaporated in vacuo to give benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]glycolate(a mixture of epimers at 2 position) (440 mg). This product wasidentified with that obtained in Example 2(a)-(6).

(a)-(8) A solution of benzyl2-[2-oxo-3β-(2-phenoxyacetamido)-4β-[2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio]azetidin-1-yl]glycolate(a mixture of epimers at 2 position) (19.6 g) in methylene chloride (220ml) was cooled to -40° C. and thereto was added 2,6-lutidine (5.17 g).To the solution was added dropwise a solution of thionyl chloride (5.75g) in methylene chloride (10 ml) over a period of 20 minutes at the sametemperature and then the temperature was gradually raised to -5° C. Themixture containing benzyl2-chloro-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-[2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio]azetidin-1-yl]acetate(a mixture of epimers at 2 position) was washed with an aqueous solutionof sodium chloride and dried over magnesium sulfate. After addition oftriphenylphosphine (15.7 g), the resulting mixture was refluxed for 5.5hours. The reaction mixture was cooled and then washed with a coldaqueous solution of sodium bicarbonate (×2) and an aqueous solution ofsodium chloride, dried over magnesium sulfate and evaporated. Theresidue was subjected to column chromatography on silica gel (300 g),using a mixture of benzene and ethyl acetate (4:1) as an eluent to givean oil of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]acetate(10.65 g).

I.R. (CH₂ Cl₂): 3380, 1760, 1690, 1615 cm⁻¹.

(a)-(9) To a solution of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]acetate(12.51 g) in methylene chloride (115 ml) were added acetic acid (6.8 ml)and zinc powder (10.0 g) successively under ice cooling and then stirredfor an hour at room temperature. After addition of ethyl acetate (400ml), the reaction mixture was filtered through Celite. The filtrate waswashed with a saturated aqueous solution of sodium bicarbonate and anaqueous solution of sodium chloride, dried over magnesium sulfate andthen evaporated to give a crude product (10.4 g), which was subjected tocolumn chromatography on silica gel (90 g), using a mixture of benzeneand ethyl acetate (3:1) as an eluent to give an oil (5.6 g). Thisproduct was crystallized from benzene to give benzyl2-triphenylphosphoranylidene2-2-oxo-3β-(2-phenoxyacetamido)-4β-(2-hydroxyacetylthio)azetidin-1-yl]acetate(2.1 g). mp 128° to 132° C.

I.R. (Nujol): 3300, 3060-3180, 1770, 1680, 1600 cm⁻¹

    ______________________________________                                        Elemental Analysis:                                                                   C           H      N                                                  ______________________________________                                        Calc'd:   66.84         4.91   3.90                                           Found:    67.16         4.96   3.66                                           ______________________________________                                    

Preparation of the object compound

(b) A mixture of benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-(2-hydroxyacetylthio)azetidin-1-yl]acetate(2.04 g), acetic anhydride (8 ml) and dimethylsulfoxide (8 ml) wasstirred for 4 hours and 45 minutes at room temperature. In the course ofthe reaction, benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenoxyacetamido)-4β-(glyoxyloylthio)azetidin-1-yl]acetatewas produced. After removal of the excess acetic anhydride in vacuo, theresulting solution was poured into ethyl acetate and cold water. Theorganic layer was separated, washed with water, a diluted aqueoussolution of sodium bicarbonate and an aqueous solution of sodiumchloride in turn, dried over magnesium sulfate and then evaporated. Theresidual oil was subjected to column chromatography on silica gel (24 g)and eluted first with benzene and then with a mixture of benzene andethyl acetate (9:1) to give an amorphole solid, which was crystallizedby diethyl ether to give of benzyl7β-(2-phenoxyacetamido)-2-oxo-3-cephem-4-carboxylate (0.80 g). mp.127°-128° C.

I.R. (CH₂ Cl₂): 3390, 1805, 1735, 1700, 1655 cm⁻¹

N.M.R. (DMSO-d₆,δ): 4.63 (2H, s), 5.36 (2H, s), 5.86 (1H, dd, J=5 and 8Hz), 6.05 (1H, d, J=5 Hz), 6.33 (1H, s), 6.88-7.05, 7.20-7.50 (10H, m),9.36 (1H, d, J=8 Hz).

    ______________________________________                                        Elemental Analysis:                                                                     C    H          N      S                                            ______________________________________                                        Calc'd:     60.26  4.13       6.39 7.31                                       Found:      60.63  4.12       6.29 7.08                                       ______________________________________                                    

U.V. (Dioxane) λmax 314 (ε=6022), 277 (ε=4196), 270 (ε=3987).

EXAMPLE 4

Preparation of the starting compounds

(a)-(1) A mixture of 2-oxo-3β-(2-phenylacetamido)-4β-mercaptoazetidine(4.72 g), 2-(2,2,2-trichloroethoxycarbonyloxy)acetyl chloride (9.38 g)and methylene chloride (25 ml) was cooled to 0° C. and pyridine (2.21 g)was added thereto with stirring and then the stirring was continued foran hour at the same temperature. The reaction mixture was diluted withethyl acetate (120 ml) and poured into ice-water (120 ml). The organiclayer was separated, washed successively with 2% hydrochloric acid (30ml), water (30 ml), 2% aqueous solution of sodium bicarbonate (30 ml)and water (30 ml), dried over magnesium sulfate and then evaporated invacuo. The residue was triturated with diethyl ether (150 ml) and theprecipitates were collected by filtration, washed with diethyl ether andthen dried to give2-oxo-3β-(2-phenylacetamido)-4β-[2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio]azetidine(7.60 g).

I.R. (CH₂ Cl₂): 3400, 1785, 1770, 1685 cm⁻¹

N.M.R. (DMSO-d₆ +D₂ O,δ): 3.62 (2H, s), 4.8-5.5 (5H, m), 5.63 (1H, d,J=4.5 Hz), 7.35 (5H, s).

(a)-(2) A solution of2-oxo-3β-(2-phenylacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidine(469 mg) and benzyl glyoxylate (1.64 g) in benzene (20 ml) was stirredunder reflux for 11 hours with continuous removal of water (Dean-Starkapparatus). The reaction mixture containing benzyl2-[2-oxo-3β-(2-phenylacetamido)-4β-{2-(2,2,2-trichloroethoxy)carbonyloxyacethylthio}azetidin1-yl]glycolate (a mixture of epimers at 2 position). was washedsuccessively with 10% aqueous solution of sodium bisulfite (20 ml×5),and water (×2), dried over magnesium sulfate and then evaporated. To asolution of the residual oil (1.36 g) in absolute methylene chloride (30ml), 2,6-lutidine (535 mg) was added and then the solution was cooled to0° C. After addition of thionyl chloride (600 mg) with stirring, thesolution was stirred for 45 minutes at 0° C. The reaction mixturecontaining benzyl 2-chloro-2-[2-oxo-3β-(2-phenylacetamido)-4β-{2-(2,2,2-trichloroethoxy)-carbonyloxyacethylthio}azetidin-1-yl]acetate(a mixture of epimers at 2 position) was washed with an aqueous solutionof sodium chloride (20 ml×3), dried over magnesium sulfate and thentriphenylphosphine (1.40 g) was added thereto. The resulting mixture wasrefluxed for 10 hours. The reaction mixture was washed successively with5% aqueous solution of sodium bicarbonate (30 ml) and water (30 ml×2),dried over magnesium sulfate and then evaporated. The residual oil (1.95g) was subjected to column chromatography on silica gel using a mixtureof benzene and ethyl acetate as an eluent to give benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenylacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}azetidin-1-yl]acetate(0.54 g).

I.R. (CH₂ Cl₂): 1755, 1720, 1670, 1610 cm⁻¹

(a)-(3) To a mixture of acetic acid (0.25 ml) and methylene chloride(2.5 ml), benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenylacetamido)-4β-{2-(2,2,2-trichloroethoxy-carbonyloxy)acetylthio}-azetidin-1-yl]acetate(500 mg) was added. The mixture was cooled to 10° to 15° C. and zincpowder (400 mg) was added thereto with stirring and then the stirringwas continued for an hour. The reaction mixture was filtered and thefiltrate was diluted with ethyl acetate (20 ml), washed successivelywith 5% aqueous solution of sodium bicarbonate and sodium chloride,dried over magnesium sulfate and then evaporated in vacuo to give benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenylacetamido)-4β-(2-hydroxyacetylthio)azetidin-1-yl]acetate(0.37 g).

I.R. (CH₂ Cl₂): 3300, 1760, 1690, 1610 cm⁻¹.

Preparation of the object compound

(b) To a mixture of dimethylsulfoxide (0.4 ml) and acetic anhydride (0.4ml), benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenylacetamido)4β-(2-hydroxyacetylthio)azetidin-1-yl]acetate(92 mg) was added and the mixture was stirred for 6.5 hours at roomtemperature. In the course of the reaction, benzyl2-triphenylphosphoranylidene-2-[2-oxo-3β-(2-phenylacetamido)-4β-(glyoxyloylthio)azetidin-1-yl]acetatewas produced. The reaction mixture was concentrated in vacuo and theresidue was dissolved in ethyl acetate (20 ml). The ethyl acetate layerwas separated, washed successively with ice-water, 2% aqueous solutionof sodium bicarbonate and water, dried over magnesium sulfate and thenevaporated in vacuo. The residue was subjected to column chromatographyon silica gel, using a mixture of benzene and ethyl acetate (3:1) as aneluent to give a foam of benzyl7β-(2-phenylacetamido)-2-oxo-3-cephem-4-carboxylate (12 mg).

I.R. (CH₂ Cl₂): 3400, 1800, 1730, 1690, 1650 cm⁻¹

N.M.R. (CDCl₃,δ): 3.60 (2H, s), 5.26 (2H, s), 5.62 (1H, d, J=4 Hz), 5.80(1H, dd, J=4 and 8 Hz), 6.36 (1H, s), 6.60 (1H, d, J=8 Hz), 7.0-7.4(10H, m).

EXAMPLE 5

To a solution of benzyl7β-(2-phenoxyacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylate (379mg.) in methylene chloride (10 ml.) were added N,N-dimethylaniline (218mg.) and phosphorus pentachloride (373 mg.) at -40° C. followed bystirring at about -35° C. for 50 minutes. To the mixture was addedmethanol (0.6 ml.) at -55° C., and the temperature was gradually raisedto 0° C. over a period of 70 minutes. To the reaction mixture was addedwater (0.3 ml.) followed by stirring under ice-cooling for 25 minutes.The precipitates were collected by filtration, washed with a smallamount of isopropyl alcohol and then dried over phosphorus pentoxideunder reduced pressure to give benzyl7β-amino-1-oxadethia-2-oxo-3-cephem-4-carboxylate.hydrochloride (70mg.), m.p. 70° to 82° C. (dec.).

I.R. (Nujol) 1820, 1730 cm⁻¹

N.M.R. (CD₃ OD,δ) 5.24 (1H, d, J=4 Hz), 6.15 (1H, d, J=4 Hz), 5.33 (2H,s), 6.46 (1H, s), 7.4 (5H, m).

EXAMPLE 6

To a solution of benzyl7β-(2-phenoxyacetamido)-2-oxo-3-cephem-4-carboxylate (294 mg) inmethylene chloride (7 ml) were added successively N,N-dimethylaniline(0.17 ml) and phosphorus pentachloride (281 mg) at -35° C. The mixturewas stirred for 1.5 hours at -35° to -30° C. and cooled to -50° C. andthen thereto was added methanol (0.57 ml). After the temperature wasraised gradually to 0° C. over a period of 1.5 hours, water (0.5 ml) wasadded. The precipitates were collected by filtration and washed with asmall amount of isopropyl alcohol to give benzyl7βamino-2-oxo-3-cephem-4-carboxylate hydrochloride (96.5 mg).

I.R. (Nujol): 3140, 1800, 1730, 1640 cm⁻¹

N.M.R. (DMSO-d₆, δ): 5.40 (2H, s and 1H, d, J=5 Hz), 6.13 (1H, d, J=5Hz), 6.45 (1H, s), 7.45 (5H,s).

EXAMPLE 7

To a solution (1 ml.) of N,N-dimethylformamide (292 mg.) in methylenechloride (10 ml.) was added a solution (1 ml.) of phosphorus oxychloride(318 mg.) in methylene chloride (10 ml.) under ice-cooling followed bystirring at the same temperature for 80 minutes. To a mixture was added2-pentyloxyimino-2-(2-formamidothiazol-4-yl)acetic acid (syn isomer) (57mg.), and the resulting clear solution was stirred for an hour underice-cooling. On the other hand, a suspension of benzyl7β-amino-1-oxadethia-2-oxo-3-cephem-4-carboxylate-hydrochloride (50 mg.)in methylene chloride (2 ml.) was cooled to -45° C. and thereto wasadded a solution (1 ml.) of pyridine (400 mg.) in methylene chloride (10ml.). To the mixture was added immediately the clear solution obtainedabove, and the temperature was gradually raised to -5° C. over a periodof 85 minutes. After the reaction mixture was poured into a mixture ofethyl acetate (50 ml.) and cold water, the organic layer was separated.The organic layer was washed successively with cold diluted hydrochloricacid, a cold diluted aqueous solution of sodium bicarbonate and anaqueous solution of sodium chloride, dried over magnesium sulfate andthen evaporated to give a yellow oil (62 mg.). Thus obtained oil waschromatographed on silica gel (1.3 g.) and eluted with a mixture ofbenzene and ethyl acetate (3:1). The fractions containing the desiredcompound were evaporated to give benzyl7β-[2-pentyloxyimino-2-(2-formamidothiazol-4-yl)acetamido]1-oxadethia-2-oxo-3-cephem-4-carboxylate(syn isomer) (30 mg.).

I.R. (CH₂ Cl₂)

3350, 1810, 1730, 1690 cm⁻¹.

N.M.R. (CD₃ COCD₃,δ) 0.90 (3H, t, J=6 Hz), 1.1-1.9 (6H, m) 4.17 (2H, t,J=6 Hz), 5.40 (2H, s), 5.96 (1H, dd, J=4, 8 Hz), 6.20 (1H, d, J=4 Hz),6.34 (1H, s), 7.34 (1H, s), 7.43 (5H, m), 8.48 (1H, d, J=8 Hz), 8.67(1H, s), 11.50 (1H, broad).

EXAMPLE 8

The following compounds were prepared in the similar manner to thatdescribed in Example 7.

(1) Benzyl7β-(2-methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylate(syn isomer).

I.R. (CH₂ Cl₂) 3390, 1815, 1740, 1685, 1610 cm⁻¹

N.M.R. ((CD₃)₂ C=0,δ) 3.95 (3H, s), 5.40 (2H, s), 6.03 (1H, dd, J=4, 8Hz), 6.23 (1H, d, J=4 Hz), 7.33-7.83 (10-11H, m):

(2) Benzyl7β-(2-phenoxyacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylate.

I.R. (CH₂ Cl₂): 1820, 1745, 1700 cm⁻¹

(3) Benzyl7β-benzyloxycarboxamido-1-oxadethia-2-oxo-3-cephem-4-carboxylate.

I.R. (CH₂ Cl₂): 1818, 1735 cm⁻¹

(4)7β-[2-Pentyloxyimino-2-(2-formamidothiazol-4-yl)-acetamido]-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid (syn isomer).

I.R. (Nujol): 1800, 1720, 1680, 1660 cm⁻¹

(5)7β-(2-Methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid (syn isomer).

I.R. (Nujol): 3370, 1815, 1740, 1680 cm⁻¹

(6) 7β-(2-Phenoxyacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid.

I.R. (CH₂ Cl₂): 1815, 1735, 1695 cm⁻¹

(7) 7β-Benzyloxycarboxamido-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid.

I.R. (CH₂ Cl₂): 1815, 1730 cm⁻¹

(8)7β-[2-Pentyloxyimino-2-(2-aminothiazol-4-yl)-acetamido]-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid hydrochloride (syn isomer).

I.R. (Nujol): 1800, 1720, 1660, 1620 cm⁻¹

(9) Benzyl 7β-(2-phenoxyacetamido)-2-oxo-3-cephem-4-carboxylate.

I.R. (CH₂ Cl₂): 3390, 1805, 1735, 1700, 1655 cm⁻¹

(10) Benzyl 7β-(2-phenylacetamido)-2-oxo-3-cephem-4-carboxylate.

I.R. (CH₂ Cl₂): 3400, 1800, 1730, 1690, 1650 cm⁻¹

(11) 7β-(2-Phenoxyacetamido)-2-oxo-3-cephem-4-carboxylic acid.

I.R. (Nujol): 3350, 1810, 1790, 1725, 1650 cm⁻¹

(12) 7β-(2-Phenylacetamido)-2-oxo-3-cephem-4-carboxylic acid.

I.R. (CH₂ Cl₂): 1800, 1750, 1685, 1650 cm⁻¹

(13) Benzyl7β-(2-phenoxyacetamido)-1-oxadethia-2-oxocepham-4α-carboxylate.

I.R. (Nujol): 3320, 1780, 1770, 1740, 1680 cm⁻¹

(14) Benzyl7β-(2-phenoxyacetamido)-1-oxadethia-2-oxocepham-4β-carboxylate.

I.R. (Nujol): 3320, 1780, 1770, 1740, 1680 cm⁻¹

(15) Benzyl7β-(2-methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4.alpha.-carboxylate(syn isomer).

I.R. (CH₂ Cl₂): 3370, 1790, 1760, 1740, 1680 cm⁻¹

(16) Benzyl7β-(2-methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4β-carboxylate(syn isomer).

I.R. (CH₂ Cl₂): 3370, 1790, 1770, 1740, 1680 cm⁻¹

(17) Benzyl7β-benzyloxycarboxamido-1-oxadethia-2-oxocepham-4α-carboxylate.

I.R. (CH₂ Cl₂): 1800, 1770, 1730 cm⁻¹

(18) Benzyl7β-benzyloxycarboxamido-1-oxadethia-2-oxocepham-4β-carboxylate.

I.R. (CH₂ Cl₂): 1800, 1775, 1740, 1725 cm⁻¹

(19) 7β-(2-Phenoxyacetamido)-1-oxadethia-2-oxocepham-4α-carboxylic acid.

I.R. (Nujol): 3320, 1780, 1750, 1730, 1640 cm⁻¹

(20)7β-(2-Methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4.alpha.-carboxylicacid (syn isomer).

I.R. (Nujol): 1790, 1730, 1650 cm⁻¹

(21)7β-(2-Methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4β-carboxylicacid (syn isomer).

I.R. (Nujol): 3330, 1800, 1770, 1680 cm⁻¹

EXAMPLE 9

To a solution of benzyl7β-(2-phenoxyacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylate (1.16g) in methylene chloride (14 ml) were successively added acetic acid(1.7 ml) and zinc powder (1.34 g) at room temperature. The resultingmixture was stirred for 25 minutes at room temperature. The reactionmixture was diluted with ethyl acetate and then filtered through a padof Celite. The filtrate was successively washed with water, a dil.aqueous solution of sodium bicarbonate and an aqueous solution of sodiumchloride and then dried over magnesium sulfate. Evaporation of thesolution gave an amorphous solid (1.25 g), which was crystallized byaddition of benzene and a small amount of methylene chloride to givebenzyl 7β-(2-phenoxyacetamido)-1-oxadethia-2-oxocepham-4α-carboxylate(775 mg). mp. 130° to 136° C.

I.R. (Nujol): 3320, 1780, 1770, 1740, 1680 cm⁻¹

N.M.R. (CDCl₃,δ): 2.91 (2H.AB part of the ABX pattern J_(AB) =16 Hz,J_(AX) =10 Hz, J_(BY) =8 Hz), 4.50 (2H, S), 4.75 (1H, X part of the ABXpattern J_(AX) =10 Hz, J_(BX) =8 Hz), 5.20 (2H, S) 5.57 (1H, d d, J=3and 9 Hz), 5.76 (1H, d, J=3 Hz), ##EQU1## (10H, m), 7.50 (1H, d,J=9 Hz).The mother liquor was concentrated and chromatographed on silica gel (12g), and eluted with a mixture of benzene and ethyl acetate (7:1 and then4:1). From the fractions of benzene and ethyl acetate (7:1), thecrystals (16 mg) of the same compound were obtained.

Further, from the fractions of benzene and ethyl acetate (4:1), therewas obtained an oil (89 mg), which was crystallized by addition ofbenzene and diethyl ether to give benzyl7β-(2-phenoxyacetamido)-1-oxadethia-2-oxocepham-4β-carboxylate (65 mg),mp 114° to 115.5° C.

I.R. (Nujol): 3400, 1800, 1780, 1760 cm⁻¹

N.M.R. (CDCl₃,δ): 2.90 (2H, d, J=5 Hz), 4.44 (1H, d t,J=1.5 and 5 Hz),4.50 (2H, s), 5.20 (2H, s), 5.62 (1H, d d d, J=1.5 and 3.5 and 9 Hz),5.71 (1H, d, J=3.5 Hz), ##EQU2## (10H, m).

EXAMPLE 10

To a solution of benzyl7β-(2-methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylate(syn isomer) (135 mg) in methylene chloride (4 ml) were successivelyadded acetic acid (0.45 ml) and zinc powder (270 mg) at room temperatureand then the resulting mixture was stirred for 10 minutes. The reactionmixture was diluted with ethyl acetate and filtered through Celite. Thefiltrate was washed successively with water, a dil. aqueous solution ofsodium bicarbonate and an aqueous solution of sodium chloride and thendried over magnesium sulfate. Evaporation of the solution gave a foam(150 mg), which was chromatographed on silica gel (4 g) and eluted witha mixture of benzene and ethyl acetate (5:1). From the less polarfractions, there was obtained a foam of benzyl7β-(2-methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4.alpha.-carboxylate(syn isomer) (51 mg).

I.R. (CH₂ Cl₂): 3370, 1790, 1760, 1740, 1680 cm⁻¹

N.M.R. (Acetone-d₆,δ): 3.12 (2H, d, J=5 Hz), 3.93 (3H, s), 4.87 (1H, t,J=5 Hz), 5.23 (2H, s), 5.68 (1H, d d, J=3.5 and 9 Hz), 6.03 (1H, d,J=3.5 Hz), ##STR16## (10H, m), 8.45 (1H, d, J=9 Hz),

    ______________________________________                                        Elemental Analysis                                                                    C           H      N                                                  ______________________________________                                        Calc'd:   61.19         4.69   9.31                                           Found:    61.67         4.74   8.89                                           ______________________________________                                    

From the more polar fractions, there was obtained a foam of benzyl7β-(2-methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4β-carboxylate(syn isomer) (34 mg).

I.R. (CH₂ Cl₂): 3370, 1790, 1770, 1740, 1680 cm⁻¹

N.M.R. (Acetone-d_(o),δ): 3.04 (2H, AB part of the ABX pattern J_(AB)=16 Hz, J_(AX) =8 Hz, J_(BX) =4 Hz), 3.94 (3H, S), 4.65 (1H,m, X part ofthe ABX pattern), 5.19 (2H, S), 5.17 (1H, ddd, J=1.5 and 3 and 8.5 Hz),5.99 (1H, d, J=3 Hz) ##EQU3## (10H, m), 8.51 (1H, d, J=8.5 Hz),

    ______________________________________                                        Elemental Analyis                                                                     C           H      N                                                  ______________________________________                                        Calc'd:   61.19         4.69   9.31                                           Found:    60.33         4.58   9.15                                           ______________________________________                                    

EXAMPLE 11

The following compounds were obtained according to a manner similar tothose described in Examples 9-10.

(1) Benzyl7β-benzyloxycarboxamido-1-oxadethia-2-oxocepham-4α-carboxylate.

I.R. (CH₂ Cl₂): 1800, 1770, 1730 cm⁻¹

N.M.R. (CDCl₃,δ): 2.85 (2H, AB part of ABX pattern, J_(AB) =17 Hz,J_(AX) =10 Hz, J_(BX) 7 Hz), 4.68 (1H, X part of ABX pattern, J_(AX) =10Hz, J_(BX) =7 Hz), 5.11 (2H, s), 5.21 (2H, s), 5.38 (1H, d d, J=10 and3.5 Hz), 5.38 (5H, s), 5.71 (1H, d, J=3.5 Hz), 5.98 (1H, d, J=10 Hz),7.34 (5H, s). and benzyl7β-benzyloxycarboxamido-1-oxadethia-2-oxocepham-4β-carboxylate. mp 128°to 134° C.

I.R. (CH₂ Cl₂): 1800, 1775, 1740, 1725 cm⁻¹

N.M.R. (CDCl₃,δ): 2.85 (2H, d, J=5 Hz), 4.41 (1H, t, J=5 Hz), 5.13 (2H,s), 5.21 (2H, s), 5.3-5.8 (3H, m), 7.35 (5H, s), 7.37 (5H, s).

(2) 7β-(2-Phenoxyacetamido)-1-oxadethia-2-oxocepham-4α-carboxylic acid.

I.R. (Nujol): 3320, 1780, 1750, 1730, 1640 cm⁻¹

(3)7β-(2-Methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4.alpha.-carboxylicacid (syn isomer).

I.R. (Nujol): 1790, 1730, 1650 cm⁻¹

(4)7β-(2-Methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4β-carboxylicacid (syn isomer)

I.R. (Nujol): 3330, 1800, 1770, 1680 cm⁻¹

EXAMPLE 12

A solution of benzyl7β-[2-pentyloxyimino-2-(2-formamidothiazol-4-yl)acetamido]-1-oxadethia-2-oxo-3-cephem-4-carboxylate(syn isomer) (10 mg.) in a mixture of ethyl acetate (0.5 ml.) andethanol (0.5 ml.) was hydrogenated by using Pd-Black (7 mg.) for 25minutes at room temperature under atmospheric pressure. The reactionmixture was filtered to remove insoluble substances and then evaporatedto dryness to give7β-[2-pentyloxyimino-2-(2-formamidothiazol-4-yl)acetamido]1-oxadethia-2-oxo-3-cephem-4-carboxylicacid (syn isomer).

I.R. (Nujol) 1800, 1720, 1680, 1660 cm⁻¹.

N.M.R. ((CD₃)₂ C=O,δ) 0.9 (3H, t, J=6 Hz), 1.1-1.8 (6H, m), 4.16 (2H, t,J=6 Hz), 6.00 (1H, d,d, J=4, 8 Hz), 6.19 (1H, d, J=4 Hz), 6.30 (1H, s),7.49 (1H, s), 8.66 (1H, s).

EXAMPLE 13

A solution of aluminum chloride (206 mg.) in nitromethane (1.2 ml.) wasadded over 1 minute at 0° C. to a solution of benzyl7β-(2-phenoxyacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylate (134mg.) and anisole (0.5 ml.) in methylene chloride (3 ml.), and theresulting mixture was stirred for 40 minutes at 0° C. under a stream ofnitrogen. The reaction mixture was poured into ice-water and the aqueouslayer was acidified to pH 1 with 1 N hydrochloric acid. The organiclayer was extracted 3 times with methylene chloride. The extracts werecombined, washed with a saturated aqueous solution of sodium chloride,dried and evaporated to give semisolid substance (150 mg.). Thissubstance was washed 3 times with diethyl ether to give solid (92 mg.),which was triturated with ethyl acetate, filtered and washed twice withethyl acetate. The filtrate and the washings were combined together andconcentrated to give amorphous solid (66 mg.). The solid was trituratedwith diethyl ether and collected by filtration to give solid of7β-(2-phenoxyacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylic acid (42mg.).

I.R. (CH₂ Cl₂) 1815, 1735, 1695 cm⁻¹

N.M.R. (d₆ -Acetone, δ) 4.62 (2H, s), 5.84 (1H, dd, J=4, 9 Hz), 6.08(1H, d, J=4 Hz), 6.22 (1H, s), 6.7-7.6 (5H, m), 8.50 (1H, broad d, J=9Hz).

EXAMPLE 14

To a solution of benzyl7β-(2-phenoxyacetamido)-2-oxo-3-cephem-4-carboxylate (369 mg) inmethylene chloride (15 ml) were added successively anisole (1.37 ml) anda solution of aluminum chloride (560 mg) in nitromethane (5 ml) underice-cooling. The mixture was stirred for 25 minutes at the sametemperature and poured into a mixture of methylene chloride and dil.hydrochloric acid. The organic layer was separated, washed with anaqueous solution of sodium chloride, dried over magnesium sulfate andconcentrated to dryness. After addition of diisopropyl ether to theresidue, the precipitates were collected by filtration and then washedwith a small amount of diethyl ether to give7β-(2-phenoxyacetamido)-2-oxo-3-cephem-4-carboxylic acid (235 mg). mp158° to 160° C. (dec.).

I.R. (Nujol): 3350, 1810, 1790, 1725, 1650 cm⁻¹.

N.M.R. (DMSO-d₆, δ): 4.62 (2H, s), 5.82 (1H, dd, J=5 and 8 Hz), 6.01(1H, d, J=5 Hz), 6.23 (1H, s), 6.85-7.5 (5H, m), 9.38 (1H, d, J=8 Hz).

    ______________________________________                                        Elemental Analysis:                                                                    C    H           N      S                                            ______________________________________                                        Calc'd:    51.72  3.47        8.04 9.20                                       Found:     51.82  3.49        7.70 8.95                                       ______________________________________                                    

U.V. (Dioxane) 270 (ε=3950), 277 (ε=4280), 313 (ε=6090).

EXAMPLE 15

To a solution of benzyl7β-(2-phenoxyacetamido)-1-oxadethia-2-oxocepham-4α-carboxylate (50 mg)in methylene chloride (1.5 ml) was added anisole (0.195 g) followed byaddition of a solution of aluminum chloride (79 mg) in nitromethane(0.53 ml) under ice-cooling. The mixture was stirred for 35 minutes atthe same temperature and then for a further 10 minutes without anice-bath. The reaction mixture was poured into a mixture of ethylacetate and water and the aqueous layer was acidified with dil.hydrochloric acid. The organic layer was separated, washed with anaqueous solution of sodium chloride, dried over magnesium sulfate andthen evaporated. The residue was triturated with diethyl ether andprecipitates were collected by filtration and then dried to give7β-(2-phenoxyacetamido)-1-oxadethia-2-oxocepham-4α-carboxylic acid (19mg).

I.R. (Nujol): 3320, 1780, 1750, 1730, 1640 cm⁻¹.

N.M.R. (CD₃ COCD₃, δ): 3.06 (2H, d, J=8 Hz), 4.59 (2H, s), 4.65 (1H, t,J=8 Hz), 5.58 (1H, d d, J=4 and 9 Hz), 5.94 (1H, d, J=4 Hz), 6.84-7.40(5H, m), 8.16 (1H, d, J=9 Hz).

EXAMPLE 16

The following compounds were prepared in the similar manners asdescribed in Examples 12 to 15.

(1)7β-(2-Methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid (syn isomer).

I.R. (Nujol): 3370, 1815, 1740, 1680 cm⁻¹.

N.M.R. (DMSO-d₆, δ): 3.95 (3H, s), 5.75 (1H, dd, J=4,8 Hz), 6.11 (1H, d,J=4 Hz), 6.19 (1H, s), 7.35-7.75 (5H, m), 9.61 (1H, d, J=8 Hz).

(2) 7β-Benzyloxycarboxamido-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid.

I.R. (CH₂ Cl₂): 1815, 1730 cm⁻¹.

N.M.R. (acetone-d₆, δ): 5.16 (2H, s), 5.70 (1H, dd, J=4,9 Hz), 6.10 (1H,d, J=4 Hz), 6.29 (1H, s), 7.39 (6H, s), 7.80 (1H, m).

(3) 7β-(2-Phenylacetamido)-2-oxo-3-cephem-4-carboxylic acid.

I.R. (CH₂ Cl₂): 1800, 1750, 1685, 1650 cm⁻¹.

N.M.R. (CDCl₃, δ): 3.67 (2H, s), 5.63 (1H, d, J=4 Hz), 5.88 (1H, dd, J=4and 8 Hz), 6.37 (1H, s), 7.3-7.6 (6H, m).

(4)7β-(2-Methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4.alpha.-carboxylicacid (syn isomer).

I.R. (Nujol): 1790, 1730, 1650 cm⁻¹.

N.M.R. (Acetone-d₆, δ): 3.08 (2H, d, J=8 Hz), 3.93 (3H, s), 4.78 (1H, t,J=8 Hz), 5.70 (1H, d,d, J=4 and 9 Hz), 6.05 (1H, d, J=4 Hz), 7.25-7.60(5H, m), 8.4 (1H).

(5)7β-(2-Methoxyimino-2-phenylacetamido)-1-oxadethia-2-oxocepham-4β-carboxylicacid (syn isomer).

I.R. (Nujol): 3330, 1800, 1770, 1680 cm⁻¹.

N.M.R. (DMSO-d₆, δ): 2.90 (2H, AB part of ABX pattern J_(AB) =16 Hz,J_(AX) =8 Hz, J_(BX) =4 Hz), 3.93 (3H, S), 4.40 (1H, m, X part of ABXpattern), 5.53 (1H, ddd, J=1.5 and 4 and 8 Hz), 5.88 (1H, d, J=4 Hz),7.4-7.7 (5H, m), 9.67 (1H, d, J=8 Hz).

(6)7β-[2-Pentyloxyimino-2-(2-aminothiazol-4-yl)-acetamido]-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid hydrochloride (syn isomer).

I.R. (Nujol): 1800, 1720, 1660, 1620 cm⁻¹.

(7) 7-(2-phenoxyacetamido)-1-oxadethia-2-oxo-3-cephem 4-carboxylic acid

I.R. (CH₂ Cl₂): 1815, 1735, 1695 cm⁻¹.

EXAMPLE 17

7β-[2-pentyloxyimino-2-(2-formamidothiazol-4-yl)acetamido]-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid (syn isomer) (201 mg.) was dissolved in methanol (5 ml.) underice-cooling and thereto was added a solution which was prepared bydiluting conc. hydrochloric acid with methanol ten times. The mixturewas stirred for 3 hours at the same temperature and for an additional 30minutes at room temperature. The reaction mixture was evaporated todryness and the residue was triturated in diethyl ether and filtered toseparate a powder. The powder was washed with ethyl acetate, filteredand then dried to give a yellow powder of7β-[2-pentyloxyimino-2-(2-aminothiazol-4-yl)acetamido]-1-oxadethia-2-oxo-3-cephem-4-carboxylicacid hydrochloride (syn isomer) (175 mg.).

I.R. (Nujol) 1800, 1720, 1660, 1620 cm⁻¹.

N.M.R. (DMSO-d₆, δ) 0.90 (3H, t, J=6 Hz), 1.1-1.9 (6H, m), 4.16 (2H, t,J=6 Hz), 5.76 (1H, dd, J=4,8 Hz), 6.14 (1H, d, J=4 Hz), 6.28 (1H, s),6.92 (1H, s), 9.64 (1H, d, J=8 Hz).

What we claim is:
 1. Cephalosporin analogues of the formula ##STR17##wherein R¹ is amino or amino substituted with a pharmaceuticallyacceptable carboxylic acyl protective group for the amino substituentsin cephalosporin compounds or with benzyl, phenethyl or trityl, andR² iscarboxy or a pharmaceutically acceptable ester of said carboxy groupemployed in cephalosporin compounds, and pharmaceutically acceptablesalts thereof.
 2. The compound of claim 1, whereinR¹ is amino; and R² isar(lower)alkoxycarbonyl.
 3. The compound of claim 2, whereinR² isphenyl(lower)alkoxycarbonyl.
 4. The compound of claim 3, which is benzyl7β-amino-2-oxo-3-cephem-4-carboxylate or its hydrochloride.
 5. Thecompound of claim 1, wherein R¹ is amino substituted with apharmaceutically acceptable carboxylic acyl protective group for theamino substituents in cephalosporin compounds.
 6. The compound of claim5, whereinR¹ is aryloxy(lower)alkanoylamino or ar(lower)alkanoylamino;and R² is carboxy or ar(lower)alkoxycarbonyl.
 7. The compound of claim6, whereinR¹ is phenoxy(lower)alkanoylamino orphenyl(lower)alkanoylamino; and R² is carboxy orphenyl(lower)alkoxycarbonyl.
 8. The compound of claim 7, whereinR¹ isphenoxyacetamido or phenylacetamido; and R² is carboxy orbenzyloxycarbonyl.
 9. The compound of claim 8, which is7β-(2-phenoxyacetamido)-2-oxo-3-cephem-4-carboxylic acid.
 10. Thecompound of claim 8, which is7β-(2-phenylacetamido)-2-oxo-3-cephem-4-carboxylic acid.
 11. Thecompound of claim 8, which is benzyl7β-(2-phenoxyacetamido)-2-oxo-3-cephem-4-carboxylate.
 12. The compoundof claim 8, which is benzyl7β-(2-phenylacetamido)-2-oxo-3-cephem-4-carboxylate.
 13. A antimicrobialpharmaceutical composition comprising an effective amount of a compoundof claim 1 or pharmaceutically acceptable salt thereof in associationwith a pharmaceutically acceptable, substantially non-toxic carrier orexcipient.